bs dd cen_ts 14235-2002

DRAFT FOR DEVELOPMENT DD CEN/TS 14235:2002

Materials and articles in contact with foodstuffs — Polymeric coatings on metal substrates — Guide to the selection of conditions and test methods for overall migration

ICS 67.250

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DD CEN/TS 14235:2002

This Draft for Development was published under the authority of the Standards Policy and Strategy Committee on 30 January 2003

© BSI 30 January 2003

ISBN 0 580 41153 2

National forewordThis Draft for Development is the English language version of CEN/TS 14235:2002.

This publication is not to be regarded as a British Standard.

It is being issued in the Draft for Development series of publications and is of a provisional nature because of the need to develop a method of test dealing with the coatings of materials and articles in contact with food, in order to satisfy the proposed European legislation. It should be applied on this provisional basis, so that information and experience of its practical application may be obtained.

Comments arising from the use of this Draft for Development are requested so that UK experience can be reported to the European organization responsible for its conversion to a European standard. A review of this publication will be initiated 2 years after its publication by the European organization so that a decision can be taken on its status at the end of its 3-year life. Notification of the start of the review period will be made in an announcement in the appropriate issue of Update Standards.

According to the replies received by the end of the review period, the responsible BSI Committee will decide whether to support the conversion into a European standard, to extend the life of the Technical Specification or to withdraw it. Comments should be sent in writing to the Secretary of BSI Subcommittee CW/47/1, Migration from plastics, 389 Chiswick High Road, London W4 4AL, giving the document reference and clause number and proposing, where possible, an appropriate revision of the text.

A list of organizations represented on this committee can be obtained on request to its secretary.

Cross-references

The British Standards which implement international or European publications referred to in this document may be found in the BSI Catalogue under the section entitled “International Standards Correspondence Index”, or by using the “Search” facility of the BSI Electronic Catalogue or of British Standards Online.

Summary of pagesThis document comprises a front cover, an inside front cover, the CEN/TS titlepage, pages 2 to 56, an inside back cover and a back cover.

The BSI copyright date displayed in this document indicates when the document was last issued.

Amendments issued since publication

Amd. No. Date Comments

TECHNICAL SPECIFICATIONSPÉCIFICATION TECHNIQUETECHNISCHE SPEZIFIKATION

CEN/TS 14235

October 2002

ICS 67.250

English version

Materials and articles in contact with foodstuffs — Polymericcoatings on metal substrates — Guide to the selection of

conditions and test methods for overall migration

Werkstoffe und Gegenstände in Kontakt mit Lebensmitteln– Polymerebeschichtungen auf Substraten aus Metall –

Leitfaden zur Auswahl der Bedingungen und Prüfverfahrenzur Bestimmung der Gesamtmigration

This Technical Specification (CEN/TS) was approved by CEN on 28 July 2002 for provisional application.

The period of validity of this CEN/TS is limited initially to three years. After two years the members of CEN will be requested to submit theircomments, particularly on the question whether the CEN/TS can be converted into a European Standard.

CEN members are required to announce the existence of this CEN/TS in the same way as for an EN and to make the CEN/TS available. Itis permissible to keep conflicting national standards in force (in parallel to the CEN/TS) until the final decision about the possibleconversion of the CEN/TS into an EN is reached.

CEN members are the national standards bodies of Austria, Belgium, Czech Republic, Denmark, Finland, France, Germany, Greece,Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.

EUROPEAN COMMITTEE FOR STANDARDIZATIONC OM ITÉ EUR OP ÉEN DE NOR M ALIS AT IONEUROPÄISCHES KOMITEE FÜR NORMUNG

Management Centre: rue de Stassart, 36 B-1050 Brussels

© 2002 CEN All rights of exploitation in any form and by any means reservedworldwide for CEN national Members.

Ref. No. CEN/TS 14235:2002 E

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Contents

page

Foreword....................................................................................................................... ...............................................4

Introduction ................................................................................................................... ..............................................5

1 Scope ......................................................................................................................... .....................................6

2 Normative references .......................................................................................................... ..........................6

3 Terms and definitions......................................................................................................... ...........................63.1 polymeric coating ........................................................................................................... ...............................63.2 final article ............................................................................................................... .......................................73.3 sample...................................................................................................................... .......................................73.4 test specimen ............................................................................................................... ..................................73.5 test piece.................................................................................................................. .......................................73.6 conventional oven ........................................................................................................... ..............................73.7 food simulant............................................................................................................... ...................................73.8 migration test .............................................................................................................. ...................................73.9 substitute test............................................................................................................. ....................................73.10 test media ................................................................................................................. ......................................73.11 alternative test........................................................................................................... .....................................73.12 extraction tests........................................................................................................... ....................................73.13 overall migration; global migration........................................................................................ ......................73.14 reduction factor........................................................................................................... ...................................83.15 pouch ...................................................................................................................... ........................................83.16 reverse pouch.............................................................................................................. ...................................83.17 inert substrate ............................................................................................................ ....................................83.18 pressure retort or autoclave ............................................................................................... ..........................83.19 cell ...................................................................................................................... ..................................................83.20 repeatability value 'r'................................................................................................... ........................................83.21 reproducibility value 'R' ................................................................................................. ....................................83.22 repeatability conditions.................................................................................................. ....................................83.23 reproducibility conditions................................................................................................ ..................................8

4 Types of test ................................................................................................................. ..................................94.1 Migration tests............................................................................................................. ...................................94.2 Substitute tests ............................................................................................................ ..................................94.3 Alternative tests ........................................................................................................... ..................................94.4 Criteria for the use of substitute tests.................................................................................... .....................9

5 Food simulants, test media and reagents ...................................................................................... ............95.1 Aqueous food simulants ...................................................................................................... .........................95.2 Fatty food simulants........................................................................................................ ............................105.3 Test media .................................................................................................................. ..................................115.4 Reagents .................................................................................................................... ...................................11

6 Selection of food simulants ................................................................................................... .....................116.1 General..................................................................................................................... .....................................116.2 Simulating contact with all food types ...................................................................................... ................116.3 Simulating contact with specific food types................................................................................. ............116.4 Simulating contact with dry foods ........................................................................................... ..................186.5 Testing for fatty contact ................................................................................................... ...........................18

7 Migration tests, substitute tests and alternative test conditions ...........................................................197.1 Test conditions for migration tests......................................................................................... ...................197.2 Test conditions for substitute tests ........................................................................................ ...................227.3 Test conditions for alternative tests ....................................................................................... ...................24

8 Apparatus ..................................................................................................................... ................................248.1 Specimen supports........................................................................................................... ...........................248.2 Tubes, glass rods and glass beads ........................................................................................... ................24

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8.3 Cells....................................................................................................................... ........................................248.4 Thermostatically controlled ovens or incubators ............................................................................. .......24

9 Samples and sample geometry ................................................................................................... ...............259.1 Samples ..................................................................................................................... ...................................259.2 Surface to volume ratio ..................................................................................................... ..........................259.3 Single surface versus double surface testing (by total immersion) ......................................................259.4 Single surface testing using a cell......................................................................................... ....................269.5 Single surface testing by pouch ............................................................................................ ...................269.6 Single surface testing using a reverse pouch ................................................................................ ..........279.7 Single surface testing by filling........................................................................................... .......................279.8 Articles intended for repeated use.......................................................................................... ...................279.9 Caps, closures and other sealing devices .................................................................................... ............289.10 Food and beverage cans..................................................................................................... ........................289.11 Non-stick coatings......................................................................................................... ..............................299.12 Flexible films ............................................................................................................. ...................................299.13 Large containers ........................................................................................................... ...............................299.14 Inert substrates ........................................................................................................... .................................299.15 Tubing, taps, valves and filters ........................................................................................... .......................299.16 Articles of irregular shape ................................................................................................ ..........................29

10 Overall migration test methods with fatty food simulants ..................................................................... .3010.1 Extraction solvents........................................................................................................ ..............................3010.2 Incomplete extraction of fat............................................................................................... .........................3010.3 Substances which interfere with gas chromatography......................................................................... ..3010.4 Loss of volatile substances................................................................................................ ........................3010.5 Gas chromatographic columns................................................................................................ ..................3110.6 Changes in the C18/C16 ratio ............................................................................................... ......................3110.7 Initial mass of the test specimen .......................................................................................... .....................3210.8 Final mass of the test specimen ............................................................................................ ....................3310.9 Selection of the appropriate conditioning procedure........................................................................ ......3310.10 Loss of simulant due to permeation ........................................................................................ ..................34

11 Precision.................................................................................................................... ...................................34

12 Test reports ................................................................................................................. .................................3412.1 Surface to volume ratios in actual use..................................................................................... .................3412.2 Reduction factors .......................................................................................................... ..............................3512.3 Validity of results ........................................................................................................ .................................3612.4 Test report ................................................................................................................ ....................................3612.5 Statements of compliance ................................................................................................... .......................36

13 Test method for overall migration into aqueous simulants by article filling from polymericcoatings on food and beverage cans and non-stick coatings................................................................37

13.1 Scope ...................................................................................................................... ......................................3713.2 Principle.................................................................................................................. ......................................3713.3 Reagents................................................................................................................... ....................................3713.4 Apparatus .................................................................................................................. ...................................3713.5 Preparation of test specimens .............................................................................................. .....................3813.6 Procedure .................................................................................................................. ...................................3913.7 Expression of results ...................................................................................................... ............................4013.8 Test report ................................................................................................................ ....................................43

Annex A (normative) Characteristics of fatty food simulants and test media....................................................44

Annex B (normative) Limit deviations on contact times and contact temperatures applicable to allclauses of this Technical Specification........................................................................................ .............46

Annex C (normative) Supports and cells........................................................................................................... .....48

Bibliography ................................................................................................................... ...........................................56

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Foreword

This document (CEN/TS 14235:2002) has been prepared by CEN/TC 194 "Utensils in contact with food", thesecretariat of which is held by BSI.

This document has been prepared under a mandate given to CEN by the European Commission and the EuropeanFree Trade Association.

In this Technical Specification the annexes A, B and C are normative.

This Technical Specification includes a Bibliography.

According to the CEN/CENELEC Internal Regulations, the national standards organizations of the followingcountries are bound to announce this Technical Specification: Austria, Belgium, Czech Republic, Denmark,Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands, Norway, Portugal,Spain, Sweden, Switzerland and the United Kingdom.

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Introduction

No single test method has been devised which can be used to determine overall migration, at all temperatures, inall food simulants. Indeed, owing to the practical difficulties inherent in testing with involatile extractants such asfats and the multitude of applications in which polymeric coatings on metal substrates come into contact with food,there are many methods and permitted variations to methods in this Technical Specification.

This Technical Specification is intended to give advice on the selection of the most appropriate type of test, testconditions and test method for a given application of a polymeric coating on a metal substrate and is intended to beread in its entirety before testing protocols are finalized. A test method for overall migration into aqueous simulantsby article filling from polymeric coatings on food and beverage cans and non-stick coatings is given in clause 12.For many polymeric coated articles methods in EN 1186-2 to EN 1186-9 are suitable, according to the form inwhich the article is tested.

The general criteria for the operation and assessment of testing laboratories as well as the general criteria forlaboratory accreditation bodies are set out in EN 45001, EN 45002 and EN 45003. It is recommended thatlaboratories using this Technical Specification validate their procedures by testing certified reference samples andby taking part in a proficiency scheme. Suitable proficiency schemes are operated in Germany and in the UnitedKingdom, for example the German Assessment Scheme for Food Testing (GAFT) and the Food AnalysisPerformance Assessment Scheme (FAPAS) conducted by the Central Science Laboratory of the Ministry ofAgriculture, Fisheries and Food.

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1 Scope

This Technical Specification gives guidelines for the selection of the appropriate conditions and test methods forthe determination of overall migration into food simulants and test media from polymeric coatings on metalsubstrates which are intended to come into contact with foodstuffs and a test method for overall migration intoaqueous simulants by article filling from polymeric coatings on food and beverage cans and non-stick coatings.

NOTE Polymeric coatings on metal substrates are not yet included in the scope of any European Union Directive. ThisTechnical Specification has been prepared to assist in the development of such a Directive.

2 Normative references

This Technical Specification incorporates by dated or undated reference, provisions from other publications. Thesenormative references are cited at the appropriate places in the text and the publications are listed hereafter. Fordated references, subsequent amendments to or revisions of any of these publications apply to this TechnicalSpecification only when incorporated in it by amendment or revision. For undated references the latest edition ofthe publication referred to applies (including amendments).

EN 1186-2, Materials and articles in contact with foodstuffs - Plastics - Part 2: Test methods for overall migrationinto olive oil by total immersion.

EN 1186-3, Materials and articles in contact with foodstuffs - Plastics - Part 3: Test methods for overall migrationinto aqueous food simulants by total immersion.

EN 1186-4, Materials and articles in contact with foodstuffs - Plastics - Part 4: Test methods for overall migrationinto olive oil by cell.

EN 1186-5, Materials and articles in contact with foodstuffs - Plastics - Part 5: Test methods for overall migrationinto aqueous food simulants by cell.

EN 1186-6, Materials and articles in contact with foodstuffs - Plastics - Part 6: Test methods for overall migrationinto olive oil using a pouch

EN 1186-7, Materials and articles in contact with foodstuffs - Plastics - Part 7: Test methods for overall migrationinto aqueous food simulants using a pouch.

EN 1186-8; Materials and articles in contact with foodstuffs - Plastics - Part 8: Test methods for overall migrationinto olive oil by article filling.

EN 1186-12, Materials and articles in contact with foodstuffs - Plastics - Part 12: Test methods for overall migrationat low temperatures.

EN 1186-13, Materials and articles in contact with foodstuffs - Plastics - Part 13: Test methods for overall migrationat high temperatures.

ISO 648 Laboratory glassware - One-mark pipettes

3 Terms and definitions

For the purposes of this Technical Specification the following terms and definitions apply.

3.1 polymeric coatingorganic material applied in the form of a continuous film on a substrate in such a way as to form a protective layerand/or a functional barrier between food and substrate. They may be applied to the substrate in the form ofsolution, dispersions, powders, or solvent free preparations.

NOTE This may be different to the definition which is expected to be included in Commission Directive 90/128/EEC whenits scope is extended to include polymeric coatings

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3.2 final articlearticle in its ready-for-use state or as sold

3.3 samplematerial or article under investigation

3.4 test specimenportion of the sample on which a test is performed

3.5 test pieceportion of the test specimen

3.6 conventional ovenoven where the air within the oven is heated and this heat is then transferred to the food through the final article asopposed to a microwave oven where the food itself is heated directly by microwave irradiation

3.7 food simulantmedium intended to simulate a foodstuff (see clauses 3 and 4)

3.8 migration testtest for the determination of overall migration using food simulants under conventional test conditions

3.9 substitute testtest carried out which uses test media under conventional substitute test conditions when the use of a migrationtest is not feasible

3.10 test mediasubstances used in "substitute tests", iso-octane, 95 % ethanol in aqueous solution and modified polyphenyleneoxide

3.11 alternative testtests, with volatile media, that may be used instead of migration tests with fatty food simulants

3.12 extraction teststests in which media having strong extraction under very severe test conditions are used

3.13 overall migration; global migrationmass of material transferred to the food simulant or test media as determined by the relevant test method

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3.14 reduction factornumbers, 2 to 5, which may be applied to the result of the migration tests relevant to certain types of fatty foodstuffsand which is conventionally used to take account of the greater extractive capacity of the simulant for suchfoodstuffs

3.15 pouchreceptacle of known dimensions manufactured from film to be tested, which when filled with food simulant exposesthe food contact side of the film to the food simulant or test medium

3.16 reverse pouchpouch, which is fabricated such that the surface intended to come into contact with foodstuffs is the outer surface.All of its sides are sealed to prevent the inner surfaces coming into contact with the food simulant. The reversepouch is intended to be totally immersed in food simulant or test medium

3.17 inert substratematerial (e.g. silver, platinum, stainless steel, tantalum) which is non-reactive in the food simulant and which cansimulate the intended metal substrate when coated with the test material. It is necessary that the inert substratedoes not interfere with the overall migration from the coating under the applied test conditions

3.18 pressure retort or autoclavepressure vessel (complying with appropriate pressure vessel regulations) in which hermetically sealed containers(e.g. metal plastics, glass) may be safely heated in a controlled manner, typically up to 122 �C and above, andwhich has suitable controlled cooling facilities

3.19celldevice in which a film or flat sheet to be tested can be mounted which when assembled and filled with foodsimulant, exposes the food contact side of the film to the food simulant or test medium

3.20repeatability value 'r'value below which the absolute difference between two single test results obtained under repeatability conditionsmay be expected to lie with a probability of 95 %

3.21reproducibility value 'R'value below which the absolute difference between two single test results obtained under reproducibility conditionsmay be expected to lie with a probability of 95%.

3.22repeatability conditionsconditions where mutually independent test results are obtained with the same method on identical test material inthe same laboratory by the same operator using the same equipment within short intervals of time

3.23reproducibility conditionsconditions where test results are obtained with the same method on identical material in different laboratories withdifferent operators using different equipment.

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4 Types of test

4.1 Migration tests

"Migration" tests for the determination of overall migration are carried out using the "food simulants" and"conventional migration test conditions", see 4.1, 4.2 and Table 1.

4.2 Substitute tests

If the migration test using fatty food simulants is not feasible, for technical reasons connected with the test method,"substitute tests" which use test media under the conventional substitute test conditions may be appropriate. Thesubstitute tests involve the use of all of the substitute test media, 95 % ethanol in aqueous solution, iso-octane andmodified polyphenylene oxide under the test conditions corresponding to the test conditions for simulant D, seeTable 4. A new test specimen is used for each test. The reduction factors, 2 to 5, are applicable to these substitutetests, see clause 5. To ascertain compliance with the overall migration limit the highest value obtained using all ofthe test media is selected.

4.3 Alternative tests

4.3.1 "Alternative tests" with volatile media

The results of alternative tests, using volatile test media such as iso-octane and 95 % ethanol in aqueous solutionor other volatile solvents or mixtures of solvents may be used to demonstrate compliance with the legislative limit,provided that:

a) the result obtained in a comparison test shows that the value is equal to or greater than those obtained in themigration test with a fatty food simulant;

b) the migration in the alternative test does not exceed the overall migration limit, after application of appropriatereduction factors.

If either or both conditions are not fulfilled, then the migration tests (3.1) have to be performed.

4.3.2 Extraction tests

Other tests are permitted which use other test media having very strong extractive power under severe testconditions, if it is generally recognized, on the basis of scientific evidence, that the results obtained using theseextraction tests are equal to or higher than those obtained with simulant D.

4.4 Criteria for the use of substitute tests

The use of substitute tests is justified, when the migration test carried out with each of the possible simulants D isfound to be inapplicable due to technical reasons connected with the migration test, e.g. interferences, incompleteextraction of oil, absence of stability of the weight of the polymeric coating, excessive absorption of fatty foodsimulant, reaction of components with the fat.

5 Food simulants, test media and reagents

5.1 Aqueous food simulants

The aqueous food simulants shall be of the following quality:

- distilled water or water of equivalent quality, simulant A;

- 3 % acetic acid (w/v) in aqueous solution, simulant B;

- For the purposes of this Technical Specification this means a solution prepared by diluting 30 g of acetic acidwith distilled water to a volume of 1 l;

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- 10 % ethanol (v/v) in aqueous solution, simulant C.

For liquids or beverages with an ethanol content greater than a volume fraction of 10 % the test is carried out withaqueous solutions of ethanol of a similar strength.

Each of the above food simulants shall give a non-volatile residue of less than 5 mg/l, when evaporated to drynessand dried to constant weight at 105 °C to 110 °C.

For overall migration testing of a coating material which is applied to substrates which are not resistant to acid, 3 %acetic acid is an unsuitable simulant because of the interfering corrosion products. 10 % aqueous ethanol shouldbe used instead, since intensive studies have demonstrated that they provide sufficient information to evaluatecoating materials for the overall migration properties even under the condition of contact with acidic food.

Only in certain cases would it appear necessary to use 3 % acetic acid as simulant, e.g. for samples containinginorganic constituents and testing specific migration of certain additive such as pigments, siccatives, amines andsimilar. In these cases the finished product can be tested with acetic acid only if the corrosion products do notinterfere with the determination of the particular specific migrant. Otherwise it is recommended either to apply thecoating on to an inert substrate prior to testing, or to test the unsupported film in the case of laminated metal.

5.2 Fatty food simulants

The fatty food simulants are as follows:

- rectified olive oil, "reference simulant D".

This "reference simulant D" may be replaced by a synthetic mixture of triglycerides or sunflower oil or corn oil withstandardized specifications. These are known as "other fatty food simulants" and called "simulant D".

For the characteristics of olive oil, a synthetic mixture of triglycerides, sunflower oil and corn oil, see annex A.

NOTE When these fatty food simulants are used to simulate some classes of food, reduction factors may be used, see 5.3and Table 2.

When determining the overall migration from materials and articles the mixtures of fatty acid triglyceridesconventionally chosen to simulate fatty food have a number of shortcomings, as follows:

- they are not a single chemical compound and composition can vary even within the permitted specification.The naturally occurring unsaturated fatty acid triglycerides can change upon storage. This allows thepossibility of inconsistent results;

- they cannot be evaporated to dryness without decomposition and therefore direct determination of the overallmigration by weighing the residue after evaporation is not feasible. An inherently less accurate and more timeconsuming indirect determination is required;

- they are absorbed by the polymeric coating under test to a varying extent. If the absorption is excessive, thisleads to gross inaccuracies in the determination. If the olive oil is not readily extractable errors also can occur.Errors can also occur if the different components of the fatty acid triglyceride are absorbed and extracted fromthe polymeric coating to a varying degree. Furthermore, substances present in the polymeric coating caninterfere with the gas chromatographic determination of olive oil as described in EN 1186-2, EN 1186-4, EN1186-6 and EN 1186-8;

- fatty acid triglycerides pose safety hazards when used at high temperatures both from the possibility of fireand the dangers of handling hot liquids;

- testing of thin layer coatings, such as used as protective coatings in cans, collapsible tubes and similararticles, does not give reliable results. The overall migration which could be expected under worst caseconditions if of about the same order of magnitude as the accuracy of the method (3 mg/dm2). The olive oilprocedure is difficult to apply to cans with double seamed or heat sealed ends, and it cannot be applied tofinished articles of greater dimension or weight.

For these reasons alternatives are desirable which should, as far as possible, avoid the deficiencies arising withtriglycerides while still giving levels of migration comparable with, but not less than, that obtained with fatty acidtriglycerides. Alternative fatty food simulants when compared with fatty food or existing fatty food simulants should

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possess the following characteristics:

- they should penetrate polymeric coating to the same extent;

- they should be as good a solvent for ingredients of polymeric coatings;

- they should be single substances or clearly defined mixtures.

5.3 Test media

5.3.1 Test media for substitute tests

The test media to be used in substitute tests are iso-octane, 95 % ethanol in aqueous solution and a modifiedpolyphenylene oxide (MPPO). The characteristics of modified polyphenylene oxide are to be found in annex A.

5.3.2 Test media for alternative tests

These are volatile media such as iso-octane and 95 % ethanol in aqueous solution or other volatile solvents ormixtures of solvents.

5.4 Reagents

Unless otherwise required, reagents shall be of analytical quality.

NOTE Specifications for solid reagents, used as such in discrete quantities, may not address suitability for use in methodsof analysis in this Technical Specification. Solid reagents may not be homogeneous with respect to contaminants notaddressed by specifications, therefore it may be necessary to demonstrate that such reagents are suitable for use.

6 Selection of food simulants

6.1 General

NOTE Commission Directive 85/572/EEC [6] specifies the use of a volume fraction of 15 % ethanol in aqueous solution assimulant C. This has been superseded by Commission Directive 97/48/EC [5} the second amendment to Council Directive82/711/EEC [3] that specifies a volume fraction of 10 % ethanol in aqueous solution.

6.2 Simulating contact with all food types

Where a polymeric coating on a metal article is intended for use in contact with all types of food it shall be testedwith a volume fraction of 3 % acetic acid in aqueous solution, simulant B, a volume fraction of 10 % ethanol inaqueous solution, simulant C and a fatty food simulant, simulant D, without reduction factors, except when thecoating material is applied to a substrate which is not resistant to acid then testing with a volume fraction of 3 %acetic acid is not required, see 4.1.

If, when using any of the other fatty food simulants, see 4.2, the migration limit is exceeded, for the judgement ofnon compliance with the overall migration limit a confirmation of the result by using olive oil is obligatory, whentechnically feasible. If this confirmation is not technically feasible and the migration from the material or articleexceeds the limit it shall be deemed not in compliance with the overall migration limit.

6.3 Simulating contact with specific food types

Provision for materials and articles intended to come into contact with specific food types has been made in thefollowing situations:

a) when the material or article is already in contact with a known foodstuff;

b) when the material or article is accompanied, by a specific indication stating with which food types it may or may

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not be used, for example "only for aqueous foods";

c) when the material or article is accompanied by a specific indication stating with which foodstuff(s) or group(s)of foodstuffs they may or may not be used. This indication shall be expressed:

1) at the marketing stage other than retail stage, by using the " reference number" or "description offoodstuffs" ;

2) at the retail stage using an indication which shall refer to only a few foods or groups of food, preferablywith examples which are easy to understand.

In situation b) the simulants to be used in the overall migration tests are specified in table 1.

Table 1 — Food simulants to be selected for testing food contact materials in special case

Contact foods Simulant

Only aqueous foods Simulant A

Only acidic foods Simulant B

Only alcoholic foods Simulant C

Only fatty foods Simulant D

All aqueous and acidic foods Simulant B

All alcoholic and aqueous foods Simulant C

All alcoholic and acidic foods Simulants C and B

All fatty and aqueous foods Simulants D and A

All fatty and acidic foods Simulants D and B

All fatty and alcoholic and aqueous foods Simulants D and C

All fatty foods and alcoholic and acidic foods Simulants D, C and B

In situation a) and c) the tests are carried out using the food simulants mentioned in Table 2.

In Table 2 for each foodstuff or group of foodstuffs, only the simulant(s) indicated by an 'X' is (are) to be used,using for each simulant, a new sample of the materials and subject concerned. Where no 'X' appears, no migrationtest is required for the heading or subheading concerned , see 5.4 on dry foods and frozen foods.

When 'X' is followed by an oblique stroke and a figure, the result of the migration tests should be divided by thenumber indicated. In the case of certain types of fatty foodstuffs, this figure, known as the 'reduction factor', isconventionally used to take account of the greater extractive capacity of the simulant for such foodstuffs.

Where a letter 'a' is shown in brackets after the 'X' only one of the two simulants given should be used:

- if the pH value is higher than 4,5, simulant A should be used;

- if the pH value is 4,5, or less, simulant B should be used.

Where a foodstuff is listed under both a specific heading and a general heading , only the simulant(s) indicatedunder the specific heading is (are) to be used.

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Where the foodstuff(s) or group(s) of foodstuffs are not included in the Table 2, select the item from the table offood simulants to be selected for testing food contact materials in special cases, which corresponds most closely tothe foodstuff(s) or group of foodstuff(s) under examination.

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Table 2 — List of simulants to be used in the migration test with a particular foodstuff or group offoodstuffs

Referencenumber a

Description of foodstuffs Simulants to be used

A B C D01

01.01

01.02

01.03

02

02.01

02.02

02.03

02.04

02.05

02.06

03

03.01

03.02

Beverages

Non-alcoholic beverages or alcoholic beverages of analcoholic strength lower than a volume fraction of 5 % :

Waters, ciders, fruit or vegetable juices of normalstrength or concentrated, musts, fruit nectars,lemonades and mineral waters, syrups, bitters,infusions, coffee, tea, liquid chocolate, beers and others

Alcoholic beverages of an alcoholic strength equal to orexceeding a volume fraction of 5 % :

Beverages shown under heading 01.01 but with analcoholic strength equal to or exceeding a volumefraction of 5 % :

Wines, spirits and liqueurs

Miscellaneous: undenatured ethyl alcohol

Cereals, cereal products, pastry, biscuits, cakes andother bakers' wares

Starches

Cereals, unprocessed, puffed in flakes, (including popcorn,corn flakes and the like)

Cereal flour and meal

Macaroni, spaghetti and similar products

Pastry, biscuits, cakes, and, other bakers' wares, dry:

A. With fatty substances on the surfaceB. Other

Pastry, cakes, and, other bakers' wares, fresh:

A. With fatty substances on the surfaceB. Other

Chocolate, sugar and products thereof Confectioneryproducts

Chocolate, chocolate-coated products, substitutes andproducts coated with substitutes

Confectionery products:

A. In solid form: I. With fatty substances on the surfaceII. Other

X(a)

X

X(a)

X b

X b

X c

X c

X/5

X/5

X/5

X/5

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Table 2 (continued)

Referencenumber a


A B C D03.02

03.03

04

04.01

04.02

04.03

04.04

04.05

05

05.01

05.02

A. In paste form: I. With fatty substances on the surfaceII. Moist

Sugar and sugar products

A. In solid formB. Honey and the likeC. Molasses and sugar syrups

Fruit, vegetables and products thereof

Whole fruit, fresh or chilled

Processed fruit:

A. Dried or dehydrated fruit, whole or in the form of flour orpowderB. Fruit in the form of chunks, purée or pasteC. Fruit preserves (jams and similar products - whole fruitor chunks or in the form of flour or powder, preserved in aliquid medium):

I. In an aqueous medium II. In an oily mediumIII. In an alcoholic medium (� a volume fraction of 5 %)

Nuts, (peanuts, chestnuts, almonds, hazelnuts, walnuts,pine kernels and other):

A. Shelled, driedB. Shelled and roastedC. In paste or cream form

Whole vegetables, fresh or chilled

Processed vegetables:

A. Dried, or dehydrated vegetables whole or in the form offlour or powderB. Vegetables, cut, in the form of puréesC. Preserved vegetables;

I. In an aqueous medium II. In an oily mediumIII. In an alcoholic medium (��a volume fraction of 5 %)

Fats and oils

Animals and vegetable fats and oil, whether natural ortreated (including cocoa butter, lard, resolidified butter)

Margarine, butter and other fats and oils made from wateremulsions in oils

X

XX

X(a)

X(a)X(a)

X

X(a)

X(a)X(a)

X(a)

X(a)X(a)X a

X(a)

X(a)X(a)X a

X

X

X/3

X

X/5 d

X/3 d

X

X

X/2

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Table 2 (continued)

Referencenumber a


A B C D 06

06.01

06.02

06.03

06.04

06.05

06.06

06.07

06.08

07

07.01

07.02

07.03

07.04

Animal products and eggs

Fish:

A. Fresh, chilled, salted, smokedB. In the form of paste

Crustaceans and molluscs (including oysters, mussels,snails) not naturally protected by their shells

Meat of all zoological species (including poultry and game):

A. Fresh, chilled, salted, smokedB. In the form of pastes or creams

Processed meat products (ham, salami, bacon and other)

Preserved and part-preserved meat and fishA. in an aqueous mediumB. In an oily medium

Eggs not in shell:A. Powdered or driedB. Other

Egg yolks:A. LiquidB. Powdered or frozen

Dried white of egg

Milk products

Milk:A. WholeB. Partly driedC. Skimmed or partly skimmedD. Dried

Fermented milk such as yoghurts, buttermilk and suchproducts in association with fruit and fruit products

Cream and sour cream

Cheeses:A. Whole, with rindB. Processed cheesesC. All others

XX

X

XX

X

X(a)X(a)

X

X

XXX

X(a)

X(a)X(a)

X(a)X(a)

X

X(a)

X(a)X(a)

X/3 d

X/3 d

X/4X/4

X/4

X

X/3 d

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Table 2 (continued)

Referencenumber a


A B C D

07.05

08

08.01

08.02

08.03

08.04

08.05

08.06

08.07

08.08

08.09

08.10

Rennet:A. in liquid or viscous formB. Powdered or dried

Miscellaneous products

Vinegar

Fried or roasted food:A. Fried potatoes, fritters and the likeB. Of animal origin

Preparations for soups broths, in liquid, solid or powderform (extracts, concentrates); homogenized compositefood preparation, prepared dishes:

A. Powdered or dried I. With fatty substances on the surfaceII. Other

B. Liquid or paste: I. With fatty substances on the surfaceII. Other

Yeasts and raising agents:A. In paste formB. Dried

Salt

Sauces:A. Without fatty substances on the surfaceB. Mayonnaise, sauces derived from mayonnaise, saladcreams and other oil in water emulsionsC. Sauce containing oil and water forming two distinctlayers

Mustard (except powdered mustard under heading 08.17

Sandwiches, toasted bread and the like containing any kindof foodstuff:A. With fatty substances on the surfaceB. Other

Ice-creams

Dried foods:A. With fatty substances on the surfaceB. Other

X(a)

X(a)X(a)

X(a)

X(a)

X(a)X(a)

X(a)

X

X(a)

X

X(a)X(a)

X(a)

X(a)

X(a)X(a)

X(a)

X/5X/4

X/5

X/3

X/3X

X/3 d

X/5

X/5

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Table 2 (concluded)

Referencenumber a


A B C D 08.11

08.12

08.13

08.14

08.15

08.16

08.17

Frozen or deep-frozen foods

Concentrated extracts of an alcoholic strength equal to orexceeding a volume fraction of 5 %

Cocoa:A. Cocoa powderB. Cocoa paste

Coffee, whether or not roasted, decaffeinated or soluble,coffee substitutes, granulated or powdered

Liquid coffee extracts

Aromatics herbs and other herbs:camomile, mallow, mint, tea, lime blossom and others

Spices and seasoning in the natural state:

cinnamon, cloves, powdered mustard, pepper, vanilla,saffron and other

X

X b X

X/5 d

X/3 d

a The source of the reference number is Council Directive 85/572/EEC [6]b This test shall be carried out only in cases where the pH is 4,5 or less.c This test may be carried out in the case of liquids or beverages of an alcoholic strength exceeding a volumefraction of 10 % with aqueous solutions of ethanol of a similar strength.d If it can be determined by means of an appropriate test that there is no 'fatty contact' with the plastics, the testwith simulant D may be dispensed with.

6.4 Simulating contact with dry foods

Polymeric coatings intended to come into contact with dry foodstuffs, such as cereals and dried eggs, or with frozenfoods, need not be tested for migration with the food simulants A, B, C and D, listed in clause 4, because theseliquid food simulants are not appropriate models (mimics) for dry and frozen foods. However, volatile substances inparticular may migrate into dry and frozen foods, especially if there is likely to be a long period of contact with theplastic. Therefore these food contact materials should be tested for the release of volatile substances. This can bedetermined in the relevant food or in a substitute food simulant. In this respect MPPO as an absorbent for thevolatile substances can be used while applying test conditions as indicated in Table 3 of 6.12.1. Another simulantthat has been used for non-polar organic substances is powdered charcoal. A third simulant that has been used totest plastics intended for contact with dry and frozen foods is silica gel which has been partially saturated with waterand which may be suitable to determine the release of polar volatile substances. None of these three simulants hasyet been fully validated and standardised for use in testing plastics for intended contact with dry and frozen foods.

6.5 Testing for fatty contact

The simulants have been specified according to the type of food the plastic is intended to contact in actual orforeseeable use. Fatty food simulants, simulant D, are used for testing polymeric coatings intended to contact fattyfoods. For certain specified food types, testing with simulant D may be dispensed with if it can be demonstrated, bymeans of an appropriate test, that there is no 'fatty contact' between the polymeric coating and the food with whichit comes into contact.

NOTE A method for determining whether a food makes fatty contact is being prepared by a Subcommittee (SC1) of TC194'Utensils in contact with food’ under work item 194077.

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The principle of the method is that food, of a similar nature to that which will contact the plastic in actual use, isplaced in contact with a polyethylene test film into which has been incorporated a fat-soluble fluorescent dye.After exposure to the film, the dye is extracted from the food and the quantity transferred from the film isdetermined by high performance liquid chromatography with fluorescence detection. The degree of transferindicates whether the food has made fatty contact with the plastic or not and hence determines whether the plasticshall be tested with simulant D or not.

The method described is suitable for direct use for a wide variety of foods. For some foods, it can be necessary tomodify the method in order to obtain results which are representative of the food/plastic contact which occurs inactual use. Examples of such foods include crisps and snack foods where the food/plastic contact area in actualuse can be small and irregular. In this instance it can be necessary to use a larger food/plastic contact area for thetest. In situations where in actual use the food can consist of different surfaces and only one surface is to contactthe food, it can be necessary to modify the method. Suitable modifications can involve altering the food so that onlythe surface that will contact the plastic in use is used for the test.

7 Migration tests, substitute tests and alternative test conditions

7.1 Test conditions for migration tests

NOTE 1 The basic rules necessary for testing the overall migration of the constituents of plastics materials and articlesintended to come into contact with foodstuffs are laid down in Council Directive 82/711/EEC and its subsequent amendments,[3], [4] and [5]).

NOTE 2 The test times and temperatures are chosen according to conditions of contact in actual use. Tolerances on contacttimes and contact temperatures applicable to all Parts of this Technical Specification are detailed in Tables B.1 and B.2.

7.1.1 General

The migration tests are to be carried out, selecting from the times and temperatures specified in table 3 thosewhich correspond to the worst foreseeable conditions of contact for the polymeric coating and to any labellinginformation on maximum temperature for use. Therefore, if the final polymeric coating is intended for a food contactapplication covered by a combination of two or more times and temperatures taken from the table, the migrationtest shall be carried out subjecting the test specimen successively to all the applicable worst foreseeable conditionsappropriate to the sample, using the same portion of food simulant.

7.1.2 Contact conditions generally recognized as more severe

NOTE In the application of the general criteria that the determination of the migration should be restricted to the testconditions which, in the specific case under examination, are recognized to be the most severe on the basis of scientificevidence, some specific examples for the test conditions are given below.

7.1.2.1 Contact with foodstuffs at any condition of time and temperature

Many articles may be used at a variety of temperatures and for varying times, or their conditions of use may not beknown. Where the polymeric coating may in actual use be employed under any conditions of contact time, and nolabelling or instructions are given to indicate contact temperature and time expected in actual use, depending onfood type(s), simulants(s) A and/or B and/or C shall be used for 4 h at 100 �C or for 4 h at reflux temperature and/orsimulant D shall be used only for 2 h at 175 �C.

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Table 3 — Conventional conditions for migration tests with food simulant

Conditions of contact in worstforeseeable use

Test conditions

Contact time Test time

t ��min see the conditions in 6.1.6

5 min < t ��h 0,5 h

0,5 h < t ��h� 1 h

1 h < t ��h 2 h

2 h < t ��h 4 h

4 h < t ��h 24 h

t> 24 h 10 d

Contact temperature Test temperature

T ��C 5 �C

5 �C < T ��C�� 20 �C

20 �C < T ��C�� 40 �C

40 �C < T ��C�� 70 �C

70 �C < T ��C 100 � C or reflux temperature

100 �C < T ��C 121 �C a

121 �C < T ��C� 130 �C a

130 �C < T ��C� 150 �C a

T > 150 �C 175 �C a

NOTE These conventional conditions for migration tests with food simulants are specified inCouncil Directive 82/711/EEC [3] as amended by D.4 and D.5.

a This temperature shall be used only for simulant D. For simulants A, B, or C the test maybe replaced by a test at 100 �C or at reflux temperature for a duration of four times the timeselected according to the general rules of 6.1.1.

7.1.2.2 Contact with foodstuffs at room temperature or below for an unspecified period

Where the materials and articles are labelled for use at room temperature or below or where the materials andarticles by their nature are clearly intended for use at room temperature and below, the test shall be carried out at40 �C for 10 days. These conditions of time and temperature are conventionally considered to be the more severe.

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7.1.3 Contact for less than 15 min at temperatures between 70 �C and 100 �C

If the polymeric coated material or article may in actual use be employed for periods of less than 15 min attemperatures between 70 �C and 100 �C, e.g. hot fill, and is so indicated by appropriate labelling or instructions,only the 2 h test at 70 �C shall be carried out. However if the material or article is intended to be used also forstorage at room temperature, the test at 70 �C for 2 h is replaced by a test at 40 �C for 10 days, this beingconventionally the more severe test.

7.1.4 Contact in a microwave oven

For materials and articles intended for use in microwave ovens, migration testing may be carried out in either aconventional oven or a microwave oven provided the appropriate time and temperature conditions are selected. Insome circumstances where arcing might occur testing of metal articles in microwave ovens may be impossible orunsafe. In these circumstances the nearest corresponding conditions of time and temperature in a conventionaloven may be appropriate. Alternatively, the coatings may be applied to an inert non metal and then tested in amicrowave oven.

NOTE A method is being prepared by a Subcommittee (SC1) of TC194 'Utensils in contact with food’, under work item194078, as a European Standard, to measure the temperature, during microwave heating and during heating in a conventionaloven , at the interface of food with packaging material.

7.1.5 Contact conditions causing changes in physical or other properties

If it is found that carrying out the test under the chosen contact conditions causes physical or other changes in thetest specimen which do not occur under worst foreseeable conditions of use of the material or article underexamination, the migration tests shall be carried out under the worst foreseeable conditions of use in which thesephysical or other changes do not take place.

7.1.6 Contact not covered by the conventional condition for migration tests

In those instances where the conventional conditions for migration tests do not adequately cover the conditions inactual use, for instance contact at temperatures greater than 175 �C or contact times of less than 5 min, othercontact conditions may be used which are more appropriate to the case under examination, provided that theselected conditions represent the worst foreseeable conditions of contact.

7.1.7 Testing at low temperatures

Testing with fats at 5 �C can lead to technical problems if the fat partially solidifies or, in the case of the synthetictriglyceride mixture, totally solidifies.

A sunflower oil, which is free of components which solidify at the temperature of test (i.e. a "dewaxed" oil ), may beused.

However, with olive oil and sunflower oil the test is usually without this problem at 10 �C. If the overall migrationdoes not exceed the limit when tested at 10 �C this indicates that it would not have exceeded the limit at 5 �C.

Testing by total immersion is practicable at low temperatures,

The method of test for the determination of overall migration from plastics at low temperatures (5 �C and 20 �C) isgiven in EN 1186-12.

7.1.8 Testing at high temperature

In practice, severe difficulties have been found in obtaining consistent and comparable results in interlaboratorytrials with the test conditions for simulating exposure at temperatures of use in excess of 121 �C. The main sourceof inconsistency appears to be due to variation in the time required to achieve the test temperature with olive oiland other fatty food simulants. Various options such as exposure of sample tubes in electrically heated cells, etc.are under investigation as possible solutions to the problem and have been incorporated in methods described inEN 1186-13, see also 6.2 for substitute tests and 6.3 for alternative tests.

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7.1.9 Food and beverage cans

By derogation from the conditions provided in the table 3, if the material or article is metal packaging, which inactual use be heat processed for two or more hours or at temperatures of 130 °C or above, it is appropriate toapply only the real conditions of use as the test conditions. The materials and articles shall be labelled accordingly.

7.1.10 Caps, gaskets, stoppers or similar sealing devices and lids

Closure sealants shall also be subjected to these conditions, although they should be tested as part of the finalarticle. Alternatively, they can be tested in a simulated manner, e.g. closed on to the neck of an articlemanufactured from an inert substance. This ensures that the closure sealant is only exposed to the simulant aswould occur in practice.

For metal ends for processed foodstuffs, the end lining compound is entrapped in the mechanically formed doubleseam and, in most cases, is not in contact with food. It is, therefore, not necessary to carry out overall migrationtests. Only were it is demonstrated that food contact occurs is testing required under the conditions of actual use.

7.1.11 Tubing, taps, valves, filters

Defining the time of exposure may be difficult for articles such as tubing, taps, valves, filters etc. as they may be incontact with flowing foodstuff. However, this exposure may be considered to be repeated brief contact for thepurposes of migration testing. Such articles may be tested by repeated total immersion or by repeated filling.Tubing may be stoppered with an inert stopper. To select the exposure time for tubing, the retention time of thefoodstuff, which is subject to the flow rate of the foodstuff, as well as length and diameter of the tubing, shall betaken into account.

7.2 Test conditions for substitute tests

Corresponding conventional conditions for the substitute tests have been agreed for examples of the mostimportant conventional migration test conditions, see Table 4.

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Table 4 — Conventional conditions for substitute tests

Test conditions withsimulant D

Test conditions with iso-octane

Test conditions withethanol 95 %

Test conditions withMPPO a

10 d at 5 �C 0,5 d at 5 �C 10 d at 5 �C -

10 d at 20 �C 1 d at 20 �C 10 d at 20 �C -

10 d at 40 �C 2 d at 20 �C 10 d at 40 �C -

2 h at 70 �C 0,5 h at 40 �C 2 h at 60 �C -

0,5 h at 100 �C 0.5 h at 60 �C b 2,5 h at 60 �C 0,5 h at 100 �C

1 h at 100 �C 1,0 h at 60 �C b 3,0 h at 60 �C b 1 h at 100�C

2 h at 100�C 1,5 h at 60 �C b 3,5 h at 60 �C b 2 h at 100 �C

0,5 h at 121 �C 1,5 h at 60 �C b 3,5 h at 60 �C b 0,5 h at 121 �C

1 h at 121 �C 2,0 h at 60 �C b 4,0 h at 60 �C b 1 h at 121 �C


0,5 h at 130 �C 2,0 h at 60 �C b 4,0 h at 60 �C b 0,5 h at 130 �C




NOTE 1 These conventional conditions for substitute tests are specified in Commission Directive 97/48/EC[5] the second amendment to Council Directive 82/711/EEC [3].

NOTE 2 Since conducting a 12 h test may pose organizational problems to a laboratory, a prolonged test, forexample of a more manageable 16 h, may be applied. This is acceptable as long as the overall migration limit isnot exceeded under such more severe test conditions.

a MPPO = modified polyphenylene oxide

b The volatile tests media are used up to a maximum temperature of 60 �C. A precondition of usingthe substitute tests is that the material or article will withstand the test conditions that wouldotherwise be used with simulant D. Immerse the test specimen in olive oil under the appropriateconditions. If the physical properties are changed (e.g. melting, deformation) then the material isconsidered unsuitable for use at that temperature. If the physical properties are not changed thenproceed with the substitute tests using new specimens.

Other test conditions may be used. In this case the examples detailed above shall be taken into account as well asexisting experience for the type of polymer under examination.

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7.3 Test conditions for alternative tests

7.3.1 Alternative test with volatile media

The test conditions for alternative tests using volatile test media such as iso-octane and 95 % ethanol in aqueoussolution or other volatile solvents or mixtures of solvents are chosen so that:

a) the result obtained in a comparison test shows that the value is equal to or greater than those obtained in themigration test with a fatty food simulant;

b) the migration in the alternative test does not exceed the migration limits, after application of appropriatereduction factors, see clause 5.

If either or both conditions are not fulfilled, then the migration tests with fatty food simulants have to be performed.

7.3.2 Extraction tests

The test conditions are selected so that the results obtained using these extraction tests are equal to or higher thanthose obtained with simulant D.

8 Apparatus

8.1 Specimen supports

In the methods for determining overall migration by total immersion, cruciform specimen supports, see Figure C.1,are specified, but other supports may be used providing they are capable of holding and keeping the test piecesapart and at the same time ensuring complete contact with the simulant. An example of a type of support that hasbeen used successfully, particularly for thick and very thin samples, which are wound around the support, is shownin Figure C.2. This type of support when loaded with the specimens is exposed to the simulants in 100 ml beakers.The beaker is then covered with a watch glass.

8.2 Tubes, glass rods and glass beads

In several of the methods for determining overall migration by total immersion the samples are tested at a fixedratio of surface area of test specimen to food simulant volume. In order to ensure that all parts of the test specimenare in contact with the food simulant, glass tubes of the appropriate diameter are used. The dimensions of thesuitable tubes are specified in the individual methods. However, minor adjustments to the level of the simulant inthe tubes may be made by adding glass rods or glass beads sufficient to ensure complete immersion of all of thesurfaces of the test specimen. Again the dimensions of suitable glass rods and glass beads are specified in theindividual methods.

8.3 Cells

In the methods recommended this Technical Specification, the availability of cell type A, as shown in Figure C.3,has been assumed. Alternative cells shall be of such design to give satisfactory performance, particularly freedomfrom leakage with all four food simulants to prevent contamination of the food simulant with non-volatilesubstances, and with minimum area of the test specimen not in direct contact with the food simulant. Examples ofother cells that are available, and have been found to be suitable, are type B, type C, type D, type E and type F;these are shown in Figures C.4, C.5, C.6, C.7 and C.8 of EN 1186-1:2001 respectively.

8.4 Thermostatically controlled ovens or incubators

Experience has shown that close temperature control is essential to obtain repeatable results. Therefore care hasto be exercised in selecting ovens or incubators to ensure that the temperature control is that specified in the TableB.2 throughout the volume of air encompassing the sample tubes, cells or pouches.

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9 Samples and sample geometry

9.1 Samples

The sample taken for compliance testing is the final article, in its ready-for-use state. In some cases this may beimpracticable and specimens can be taken from the material, article or, where appropriate, specimensrepresentative of this material or article can be used.

An example is where an article is filled with food at the time it is formed. In this case the test may be carried out ona test article prepared especially for testing purposes. This article shall be as representative as possible of thearticle in actual use.

A further example is where the sample to be tested is of inhomogeneous construction and is too large to be testedby filling and no flat surfaces can be cut from the sample for testing in a cell. In this case the test may be carried outon a test article prepared especially for testing purposes. This article shall be as representative as possible of thearticle in actual use.

Tests are also carried out on components and precursors of final articles, i.e., a coating on an inert substrateintended for can coating. These tests are carried out in order to provide guidance on the suitability of the materialfor use in the manufacture of the final article.

Where samples are taken at random from a production batch this shall be indicated when reporting the result. Thesamples shall be representative of normal production material. Similarly if the sample was not a random sample,and it was selected according to some other parameter, e.g. thickness variation, this shall also be reported.

Samples may be inhomogeneous, e.g. varying in crystallinity or in molecular orientation, or of irregular shape orthickness, e.g. sections cut from bottles, trays, work surfaces, cutlery etc., or so small that several samples arerequired to constitute a test specimen. Replicate samples as similar as possible to each other and proportionallyrepresenting the sample article shall be tested and the sampling details shall be included in the final report.

Samples shall be clean and free from surface contamination; dust may be removed by wiping the sample with alint-free cloth or brushing with a soft brush.

Some articles may be sold with instructions that they should be cleaned or treated with oils or cleaning solutionsbefore first use. In these cases the samples should be tested both before and after the treatment or cleaningprocess and the results evaluated.

In the case of treatments or cleaning carried out by the manufacturer, prior to sale, the samples should be testedafter the treatment or cleaning process.

As part of a supplier-customer agreement, a regime of good manufacturing practice may include a provision forempty unused coated metal containers intended for processed foodstuffs to be pre-rinsed with water. When this isthe standard operating procedure, then the cans should be treated similarly - either on the line or simulated in thelaboratory - prior to the standard migration tests being done.

9.2 Surface to volume ratio

Where the surface to volume ratio to be used in contact with food is known this is used in the migration testing. Anexample of this is where a bottle or other container is intended to contain a specified volume of contents even if thisdoes not completely fill the article. In this case the article is tested with the specified volume of simulant.

Where the surface to volume ratio to be used in contact with food is not known conventional conditions are used,as described in 8.3 to 8.13.

9.3 Single surface versus double surface testing (by total immersion)

Overall migration tests shall be performed in such a way that only those parts of the sample intended to come intocontact with foodstuffs in actual use will be in contact with the foodstuff or simulant. However, it is permissible todemonstrate compliance with an overall migration limit by the use of a more severe test.

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In the total immersion test, both the surface which is intended to come into contact with the foodstuff and theoutside surface are in contact with the food simulant. No allowance is made for this in the calculation of migrationper unit of surface area. Although the total surface exposed is 2 dm², only 1 dm², i.e. the food contact surface, istaken into account in the calculation. It is therefore a more severe test than testing in a pouch or in a cell or byfilling.

However, if it is possible to demonstrate experimentally that the value obtained in a total immersion test is doublethat obtained in a single surface test, the value obtained in the total immersion test shall be divided by the totalsurface area exposed.

The method for determining overall migration by total immersion with olive oil is given in EN 1186-2 and withaqueous food simulants in EN 1186-3.

9.4 Single surface testing using a cell

Where single surface testing is the preferred procedure, particularly important for multi-layer articles, this may becarried out in a cell. For samples that may be obtained in flat form, e.g. film or sheet, testing in the cell has theadvantage of readily reproducible sample geometry.

However, if testing polymeric coatings on acid resistant substrates with a volume fraction of 3 % aqueous aceticacid ensure that the materials of the cell do not influence the final result, e.g. cells constructed from aluminium maynot be suitable in contact with a volume fraction of 3 % aqueous acetic acid.

The method for the determination of overall migration in the cell into olive oil is given in EN 1186-4 and intoaqueous food simulants in EN 1186-5.

As an example the use of cell type A is described in EN 1186-4. The surface to volume ratio in the type A cell isconventionally 2,5 dm² of food contact area to 125 ml of food simulant.

Interlaboratory trials carried out by experienced laboratories have shown that consistent overall migration resultscan be obtained using cell type A.

Comparative studies carried out on the performance of cells type A, B, C, D, E and F revealed that these cells gavesimilar results. Therefore the cells referred to in Figures C.3, C.4, C.5, C.6, C.7 and C.8 are considered equivalent.

9.5 Single surface testing by pouch

For plastics films coated with metals, which have sufficient seal strength to form durable pouches, single surfacetesting in a pouch may be preferred as this does not require specialized apparatus and allows more efficient use ofoven space. Inter-laboratory collaborative testing studies using pouches of precisely specified dimensions haveshown that variations in pouch geometry (particularly varying areas outside the seals) can lead to significantvariability in the final result.

The surface to volume ratio in the pouch is conventionally 2 dm² of food contact area to 100 ml of food simulant.

The method for the determination of overall migration in a pouch into olive oil is given in EN 1186-6 and intoaqueous simulants in EN 1186-7.

NOTE For test temperatures above 40 �C it is permissible to fill the pouches with food simulant at ambient temperatureand preheat the test specimens in a microwave oven to reach the test temperature. A procedure that has been found to besuitable is to insert into the simulant of one of the test specimens a fibre optic probe or to check the temperature after heating bya thermometer. The filled pouches are placed in a microwave oven and heated until the simulant has attained the testtemperature. Remove the test specimens to a thermostatically controlled oven or incubator that is preheated to the testtemperature. This part of the operation should be carried out in the minimum time to prevent undue heat loss. Leave thepouches for the selected test period.

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9.6 Single surface testing using a reverse pouch

For thin metals coated both sides with plastics films an alternative to using a pouch, a reverse pouch may be used.In this case the surface intended to come into contact with the foodstuff is the outer surface and the pouch isexposed to the food simulant by total immersion.

The use of a reverse pouch offers advantages over the pouch. Since pouches are filled with simulant, the sealededges have to be capable of bearing the weight of that simulant; if they are not the seals give way and the pouchesare prone to leakage. With the reverse pouch the seals do not have to withstand the pressure of the simulant andconsequently are less likely to leak and the sealed area can be reduced. The use of a reverse pouch permits amore accurate determination of the area exposed to food simulant. However, it is possible that simulant may leakinto the reverse pouch thus increasing the area exposed to simulant. A way of checking if leaks have occurred is toseal into the reverse pouch a piece of filter paper which is of similar dimensions to the pouch. If the pouch leaks thepaper will absorb the simulant and this will be visible. This method may not be applicable for overall migration intofatty food simulants, as the weight of the inserted paper may change during storage due to loss of water. Anypouch that leaks shall be discarded and the test repeated.

Where the surface to volume ratio to be used in contact with food is not known, the conventional conditions areused, i.e. 2 dm² of surface in contact with 100 ml of simulant.

9.7 Single surface testing by filling

For articles in container form, e.g. cans, bottles and trays, it is often most convenient to test them by filling with foodsimulant, see clause 12, also methods for the determination of overall migration by filling with olive oil and by fillingwith aqueous food simulants are given in EN 1186-8 and EN 1186-9 respectively. For very large containers testingby filling cannot be practicable and it can be necessary to fabricate smaller test specimens representing the articleto be tested.

9.8 Articles intended for repeated use

9.8.1 Criteria for testing

It is accepted that where a material or article is intended to come into repeated contact with foodstuffs, themigration tests are carried out three times on the same test sample in accordance with the conditions laid down,using a fresh sample of the food simulant on each occasion. The compliance of the material shall be checked onthe basis of the level of the migration found in the third test. However, if there is conclusive proof that the level ofmigration does not increase in the second and third test and if the migration limit is not exceeded on the first test,no further test is necessary.

Experience has shown that some thermosetting polymers, e.g. melamine/formaldehyde resins, can give rise toincreasing levels of migration on second and subsequent exposure to foodstuffs. However, for the majority ofpolymers migration levels will fall in the second and subsequent extracts. Proof of this may be found from pastexperience with similar polymer types. For these polymeric coatings it is only necessary to show that the migrationlimit is met in the first extract

9.8.2 Aqueous simulants

For aqueous simulants, no increase in migration is deemed to have occurred if the mean of the results for thesecond and third test do not exceed the mean of the result for the first extract by more than the permitted analyticaltolerance.

9.8.3 Fatty food simulants

With fatty food simulant, the repeated exposure of the same test specimen to fresh portions of food simulant is nota feasible procedure, since the procedure requires solvent extraction to remove the fatty simulant. Therefore, thetest is carried out on three sets of test specimens from the same sample of the material or article. One of these issubjected to the test appropriate for articles intended for single use by the standard procedure and the mean resultcalculated (M1). The second and third samples are exposed in a manner identical in every respect to the firstsample except for the period of exposure. The second sample is exposed for a period of twice that of sample one

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and sample three is exposed for a period three times that of sample one. The mean result for sample 2 iscalculated (M2) as is that for sample 3 (M3).

The migration as a result of the second or third period is calculated as follows:

- migration caused by first period = M1 ;

- migration caused by the second period = M2 - M1 ;

- migration caused by the third period = M3 - M2 .

No increase in migration into fatty food simulant is deemed to have occurred if the results (M3 - M2) and (M2 - M1)do not exceed M1 by more than the analytical tolerance.

The true values for M1, M2 or M3 are subject to uncertainty owing to the lack of precision inherent in the method.Systematic errors in the determination of the overall migration are likely to apply equally to the determination of M1,M2 or M3 and therefore need not be allowed for. Random errors do need to be recognized and allowed for.

When repeated testing is used to determine the overall migration into a fatty food simulant the individual results foreach set of the determinations (M1, M2 or M3) shall be deemed valid if at least three results are obtained in each setwhich do not differ from the mean for that set by more than 30% for results above 10 mg/dm² or by more than 3mg/dm² for results below 10 mg/dm². Results which exceed this tolerance shall be discarded according to theprocedure given in 11.3.2.

When the polymeric coated material or article is intended for use with a class of foodstuff where a reduction factormay be used, this shall be applied to the individual determinations before the mean of M1 or M2 or M3 is calculated.

The material and articles are deemed to be in compliance with the overall migration limit provided that either M1 orM3 - M2 do not exceed the specified overall migration limit.

9.9 Caps, closures and other sealing devices

Caps, sealing gaskets and other sealing devices shall be tested under conditions which, as far as possible,simulate actual conditions of use.

The test is carried out on closures in the state and form in which they are intended to be used, see 6.1.10.

The simulants are placed in jars, known to give only consistently low migration, and the jars closed with the testclosures. The jars are then inverted and subjected to the test conditions appropriate for the actual conditions ofuse.

The surface to volume ratio used shall be the same as that intended for use.

For articles where the overall migration will be limited in terms of milligrams per kilogram the migration from theclosure is added to that of the container when assessing compliance with the limit.

9.10 Food and beverage cans

The finished article should be used. When closure equipment is not readily available in the laboratory, cans withdouble-seamed or heat-sealed ends may be tested using ends in which a hole has been carefully drilled. Theclosing of the empty container can be done with the equipment of the actual user. Such empty closed cans can besubsequently filled with simulants through the hole, which can then be closed by an inert stopper.

For a test method for overall migration into aqueous simulants by article filling from polymeric coatings on food andbeverage cans and non-stick coatings see clause 12.

If flat sheet material is available from which the finished articles are formed or assembled, this can be used forsingle sided tests in a suitable test cell.

In many situations, the shape, size and/or weight of the finished article are inappropriate for testing. In these casesit is advisable to apply the coating material on to an inert substrate which can be tested by total immersion, or in thecase of laminated metal to test the unsupported polymeric film. This procedure is also recommended for testing the

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coating material itself independently from the application on or for the finished article. The application of the coatingmaterial to an inert substrate should follow, as closely as possible, the conditions and specifications commensuratewith the expected production coating process.

9.11 Non-stick coatings

In the case of some coatings on thick metal substrates, e.g. non-stock cookware, it is not practicable to determinethe migration into fat simulants according to EN 1186-2 to EN 1186-8, because weight differences attributable tothe migration and absorption of fat simulant are very small in comparison to the mass of the test specimens andthus substantial errors can be expected.

In these cases, the test shall be carried out on specially prepared test specimens that are representative of thepolymeric coating on the material or article, but where the metal substrate has a mass that permits the practicableuse of the methods EN 1186-2 to EN 1186-8. Alternatively, compliance with the overall migration can bedemonstrated by the use of substitute tests using the test media iso-octane, 95 % aqueous ethanol and modifiedpolyphenylene oxide or a 'more severe test', such as extraction with solvents, such as iso-octane or 95 % aqueousethanol.

For a test method for overall migration into aqueous simulants by article filling from polymeric coatings on food andbeverage cans and non-stick coatings see clause 13.

9.12 Flexible films

With the exception of the use of 3 % aqueous acetic acid flexible plastics films coated with thin layers of metalsshould be tested in the same way as flexible plastics films and tested in accordance with the relevant Parts of EN1186.

9.13 Large containers

Large containers, where filling is not practicable, may be tested by cutting test specimens from them and testingthese by total immersion or by the cell method or using an equivalent cell.

When cutting the container is impracticable because of its size, composition, design or construction, speciallyprepared test specimens that are representative of the article or the relevant parts of the article shall be tested in acell or by total immersion.

In the case of aqueous simulants a large container may be filled and portions taken after thorough mixing, todetermine the residue. Alternatively, smaller test samples representing the large container may be fabricated andtested by filling.

9.14 Inert substrates

The application of the coating material to an inert substrate should follow, as closely as possible, the conditions andspecifications commensurate with the expected production coating process.

9.15 Tubing, taps, valves and filters

Articles such as tubing, taps, valves etc. may be in contact with flowing foodstuff, this may be considered to berepeated brief contact for the purposes of migration testing. Such articles may be tested by repeated totalimmersion or by repeated filling, tubing may be stoppered with an inert stopper.

9.16 Articles of irregular shape

Many articles which require to be tested are of irregular shape or dimensions, e.g. thickness. Examples of theseare sinks and work surfaces, eating and cooking utensils, shaped bottles and containers. When portions of thesesamples are taken for test by total immersion or in a cell care has to be exercised to ensure that the test specimensselected are representative of the whole of those parts of the article intended to come into contact with food. Also,care shall be taken to ensure that replicate test specimens are sufficiently dimensionally similar, one to another, toallow valid replication of results.

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10 Overall migration test methods with fatty food simulants

NOTE For many polymeric coated articles the test methods in EN 1186-2 to EN 1186-9 are suitable, according to the formin which the article is tested. However, the test methods detailed in EN 1186-2 to EN 1186-12 may not give reliable results incertain circumstances; these are described 9.1 to 9.10.

10.1 Extraction solvents

In previous methods for determining overall migration into fats and fatty food simulants the solvent 1,1,2, trichloro-trifluoroethane has been used to extract fat from polymeric coatings. This solvent is a member of the chloro-fluorocarbon (CFC) class of chemicals and, since every effort has been made to prevent release of this solvent tothe atmosphere, an alternative has been sought.

Pentane is the recommended extraction solvent for non-polar polymeric coatings, such as polyethylene andpolypropylene. A 95/5 by volume azeotropic mixture of pentane and ethanol is recommended as the extractionsolvent for polar polymeric coatings, such as polyamide and polyacetal

Do not discard used solvent. Re-distilled solvent, free of fat, can be used.

10.2 Incomplete extraction of fat

Incomplete extraction of absorbed fatty food simulant from some polymeric coatings occurs despite prolongedsoxhlet extraction with pentane. This is known to give falsely low results in the standard test procedure. Thisdifficulty can be overcome by subjecting the test specimens to a second extraction, this time with diethyl ether, or tothe dissolution/precipitation method set out in EN 1186-10. The amount of oil obtained in the diethyl ether extract orin the solution after precipitation of the polymer coating is added to the amount of oil obtained in the pentaneextract. To obtain reliable results the migration test shall be repeated using the dissolution/precipitation method.

10.3 Substances which interfere with gas chromatography

Some substances which may migrate from polymeric coatings are capable of interfering with the gaschromatographic method for the determination of olive oil, e.g. glyceryl oleates. When testing articles containingthese substances they may be tested with other fatty food simulants, such as sunflower oil, corn oil or synthetictriglyceride mixtures.

Other migrating substances can give rise to peaks in the gas chromatogram which interfere with the internalstandard peak. Alternative internal standards such as hydrocinnamic acid, ethyl ester or trinonadecanoin may beused in such cases.

10.4 Loss of volatile substances

During exposure of the test specimens to food simulants volatile substances such as water, solvents, monomers,oligomers etc. may be lost from the plastic. In the test procedures with aqueous food simulants further loss ofvolatile substances will occur upon evaporation of the food simulants. When the overall migration into aqueoussimulants is reported no possible loss of volatile substances is taken into account. For consistency reasons, it isconventionally agreed that also for the fat test the migration of non-volatile substances only is determined.

NOTE For the specific purpose to meet eventual health concerns about migration of organic volatiles from polymericcoatings other analytical methods such as gas chromatographic determinations of the polymeric coating headspace or solventextracts may be applied. This is currently not within the scope of conventional overall migration testing.

In the test procedures with a fatty food simulant, total or partial loss of volatile substances may occur, particularly athigh temperature. An indication of this possible loss may be deduced from:

- the loss of weight, after conditioning to constant weight at 50 % relative humidity, of the test specimens whichhave not been exposed to the fatty food simulant but have been subjected to the test temperature for the testperiod i.e. those that have been in empty tubes or pouches or test specimens which have not been filled.

- vacuum drying tests carried out for one hour at 60 �C according to the procedure set out in Annex D ofvarious Parts of EN 1186 concerned with overall migration testing using fatty food simulants.

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When a loss of volatile substances is indicated, i.e. the tolerance for weight change permitted in the appropriatesection of the test method has been exceeded, then results with correction for loss of volatile substances may bereported. The corrected overall migration figure is calculated by subtracting the mean weight loss per squaredecimetre of the test specimens not exposed to fatty food simulant from each uncorrected value calculatedaccording to the procedure in the appropriate test method. Reduction factors may then be applied (see 11.2) andthe validity of the corrected values assessed (see 11.3.2). Reported results may be based on the values withcorrection for loss of volatile substances.

10.5 Gas chromatographic columns

In the relevant Parts of EN 1186 concerning the determination of the overall migration into olive oil different types ofgas chromatographic columns are mentioned, polar and non-polar.

Column 1 is a column with a polar stationary phase that allows separation of the individual methyl esters of fattyacids according to their carbon number as well as their number of double bonds in the chain, e.g. the methyl estersof stearic acid is separated from the methyl esters of oleic acid and this is separated from the methyl esters oflinoleic acid.

Column 2 is a column with a non-polar coating which allows only separation of the carbon number, e.g. noseparation is obtained between the methyl esters of oleic acid and the methyl esters of stearic acid.

Both types of columns have their own specific advantages and disadvantages. A gas chromatogram obtained withcolumn 1 will reveal more information on the distribution of fatty acid in the olive oil extracted from the testspecimen than with column 2. To determine the total area of the fatty acids using column 1, the area of at least 5peaks may be measured and summed. With column 2 only 2 peaks have to be measured. On the other hand thedetermination will be more sensitive to interferences when using column 2. In the case where interferences occuron one of the minor peaks, when using column 1, it is possible to exclude that peak and to adapt the calibrationgraph for the excluded peak. It is even possible to measure only the major peak of oleic acid to quantify the totalamount of oil, provided the calibration graph is constructed in the same way.

NOTE A polar column is the preferred one.

Column 3, referred to in the relevant Parts of EN 1186 concerning the determination of the overall migration intoolive oil is a polar column.

10.6 Changes in the C18/C16 ratio

A difference in C18:1/C16:0 ratio (using column 1) between the olive oil extracted from the test specimen and theolive oil applied as the fatty food simulant in the migration test indicates that the composition of the extracted oil forsome reason is different from the composition of the oil that has not been in contact with a test specimen. Possiblecauses for the changes of the composition are:

- reaction of olive oil constituents with polymeric coating constituents;

- oxidation of unsaturated constituents of the olive oil. This has been observed to occur when rather longperiods for conditioning the test specimen after contact with the oil are necessary;

- incomplete methylation of fatty acids in the trans-esterification procedure, such difficulties arise with sometypes of high impact polystyrene (HIPS) and acrylonitrile-butadiene-styrene(ABS);

- selective absorption of oil constituents by test specimens. Polyolefins for example do absorb selectively mono-and diglycerides of saturated free fatty acids in some cases, whereas HIPS, ABS and nitrile-butadiene rubber(NBR) often selectively absorb diglycerides, and to a lesser extent also monoglycerides of unsaturated fattyacids;

- interface by polymeric coatings constituents having the same retention time as C16:0 or C18:1 methyl ester orforming those esters in the trans-esterification stage.

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Whether a change in the C18:1/C16:0 ratio acts upon the final result of the overall migration determination to anextent which is not acceptable depends mainly on the magnitude of the change and on the amount of oil recoveredfrom the test specimen, e.g. a 25 % change in the C18:1/C16:0 ratio may result in a 25% lower result in the amountof fat extracted, which would mean 2,5 mg when only 10 mg fat is absorbed by the test specimen but 25 mg when100 mg of fat is absorbed. So a proportional change in C18:1/C16:0 ratio will result in an absolute difference in theamount of fat calculated, and consequently in an absolute difference in the overall migration values. Whilst anabsolute difference of 2,5 mg is acceptable, because it is within the accepted analytical tolerance, one of 25 mg isnot.

Whether there might be a possibility of obtaining false results because of a change in the C18:1/C16:0 ratio, caneasily be established by measuring the amount of oil extracted from the test specimen using two differentcalibration graphs. In one graph the ratio C16:0/C17:0 is plotted versus the amount of olive oil and in the other onethe ratio C18:1/C17:0. The amount of oil calculated using the C16:0/C17:0 graph shall differ from the amountcalculated using the C18:1/C17:0 graph by no more than 2 mg/dm2. In case a larger difference is observed thecause of it has to be identified and an appropriate action be taken. Remedies for problems can be:

- if reaction of oil constituents with polymeric coating constituents is suspected a less reactive oil, e.g. asynthetic mixture of triglycerides, can be used;

- if oxidation of unsaturated fatty acids is suspected a less vulnerable fatty food simulant, e.g. a syntheticmixture of triglycerides, can be used;

- if incomplete methylation of fatty acids during trans-esterification is suspected the heptane layer obtained inthe normal trans-esterification procedure is subjected to an additional trans-esterification treatment;

- if selective absorption of fatty simulant constituents by the test specimen is suspected, which can beascertained by thin layer chromatography comparison of the composition of extracted and olive oil a fatty foodsimulant low in free fatty acids and mono- and diglycerides can be used;

- if interference of oleic acid (C18:1) or heptadecanoic acid (C17:0) peak area measurement by plasticconstituents is suspected which can be ascertained by running a blank experiment with a sample of the finalarticle in question, the palmitic acid (C16:0) peak area of olive oil can be used as a reference. It is preferablehowever to use, if possible, sunflower oil or a synthetic mixture of triglycerides as the food simulant instead.

10.7 Initial mass of the test specimen

If conditioning of test specimens is not required, the initial mass of the test specimen to be used in the formula tocalculate overall migration is simply the initial mass of the test specimen.

If it has been shown that test specimens require conditioning, they are subjected to the vacuum drying procedure orconditioning at constant relative humidity set out in Annex C and Annex B of the relevant parts of the standardsconcerned with overall migration testing using a fatty food simulant, until constant mass.

The initial mass to be used in the formula to calculate overall migration in this case is the mass of the test specimenwhen constant mass has been achieved.

When using the vacuum drying procedure, before initiating the migration experiments the test specimens aresubsequently placed at ambient humidity or in a container at 80% relative humidity until they have regained 80 % to120 % of the mass lost during vacuum drying.

The conditioning procedure at a relative humidity of 50 % as described in Annex B of the relevant parts of thisTechnical Specification can be used to establish the initial mass of the test specimen to be used in the equation tocalculate the overall migration.

Sometimes, when a number of test specimens are subjected to conditioning together, not all specimens reachconstant mass simultaneously. In such a case it is permissible to remove the test specimens that have achievedconstant mass from the conditioning device and store them until the remaining test specimens also have achievedconstant mass, before exposing all test specimens simultaneously to the food simulant.

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In selection of the conditioning technique consideration may be given to the shorter conditioning periods requiredby the vacuum drying technique in comparison with conditioning at 50 % relative humidity. Short conditioning timesare very important when the final mass of the test specimen after the migration period has been determined. Longconditioning times at room temperature in presence of oxygen will cause oxidation of the olive oil and as aconsequence the composition of the olive oil absorbed by the test specimen can change (see 9.6).

In addition, volatile substances will be removed from the test specimen and they will not interfere in the calculationof the overall migration. In this way only the migration of non-volatile substances is measured as is the case in thedetermination of the overall migration in aqueous food simulants.

10.8 Final mass of the test specimen

If conditioning of test specimens was not required to establish the initial mass of the test specimen, then the massof the test specimen after removal of the adhering oil is simply the final mass of the test specimen.

If the test specimen was conditioned before the migration period then the test specimen shall be conditioned afterthe migration period as well, using the same technique of conditioning either vacuum drying or conditioning at 50 %relative humidity. The final mass of the specimen is obtained when the difference between two consecutiveweighings is less than the permitted tolerance.

10.9 Selection of the appropriate conditioning procedure

In the relevant Parts of EN 1186 concerning test methods for overall migration testing with olive oil two procedureshave been described to establish the mass of the test specimen before and after the exposure time.

The vacuum drying method is fast and repeatable and changes in conditioning temperature will not influence thefinal mass of the test specimen. The vacuum drying method removes all volatile components and no correction forloss of volatile is required. Loss of volatiles is not usually a problem when only small amounts of volatilesubstances are present, e.g. residual monomers. If the allowed analytical tolerance of 3 mg/dm2 is taken intoaccount the removal of the volatiles will not have a significant influence on the reported overall migration. If largeamounts of volatiles are present, e.g. in expanded polystyrene, then conditioning at 50 % relative humidity has tobe taken into consideration. The major advantage of the vacuum method is the time required to establish the massof the test specimen. If the conditioning after the exposure takes a long time then the oil can oxidize and theoxidized components will not be recovered, this results in an under estimation of the overall migration.

The vacuum method is not suitable for those samples that, after drying, re-absorb the water very quickly, e.g. thickpolyamide samples. In such cases the mass will change constantly during weighing.

NOTE When following the vacuum drying procedure the mass lost during the initial conditioning may not be regained for thefollowing reasons:

- loss of mass is caused by release of water from one of the under-laying layers of a multi-layer material. It may be timeconsuming or even impossible to regain the loss of water during reconditioning. There is no objection to continue the testwithout regaining the loss of mass;

- release of a small amount of water from lipophylic polymers such as polypropylene. These type of polymers are usually notcapable of regaining the major part of the water lost. The conditioned samples can be used for overall migration testing;

- loss of mass is caused by the removal of volatile organic components. In this case the vacuum drying method may resultin too low a migration value and another method of conditioning should be used to condition the test specimen.

Conditioning at 50 % relative humidity is suitable for most types of polymers, particularly those that are subject toonly small changes in mass, and for those which are hygroscopic after vacuum drying. The procedure is alsosuitable for thin polyamide samples, whereas problems are foreseen with thick polyamide samples. The procedureof conditioning at 50 % relative humidity is usually time-consuming and can take 4 days or more. If the proceduretakes more than 7 days, then there is a possibility of oxidation of the unsaturated fatty acids and an alternativeprocedure has to be considered. The conditioning method is simple and does not require any special apparatusand can therefore be applied by any laboratory with standard equipment. Control of a specific temperature is notimportant, but the temperature needs to be kept within a very narrow range during conditioning, before and afterexposure, as the mass of test specimen is related to temperature. Correction for volatiles is allowed, but in the casewhere large quantities of volatiles are present the validity of the correction has to be carefully considered.

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Determination of the release of water from a test specimen by means of Karl-Fisher titration is also allowed as amethod of establishing the mass of the test specimen before and after exposure. Use of this method prevents theconditioning of the test specimen. This method can be useful for samples that cannot be conditioned to constantmass by one of the methods above. The method cannot be applicable to samples that release significant amountsof water resulting in over-saturation of the oil with water and subsequent loss of water through the vapour phase.

The selection of the appropriate procedure is determined by the nature of the sample and the fact that if aninappropriate procedure is adopted the result obtained may be different. The procedure used, and the reason forselecting that procedure, has to be stated in the report.

10.10 Loss of simulant due to permeation

When testing some samples by single surface testing the small amounts of simulant may permeate through thesample. For example, there may be a small loss of alcohol when testing with high strength ethanol/water simulantsby filling. In this case, as the loss in ethanol from the simulant can be expected to reflect what would happen underactual conditions of use of the alcoholic beverage, this loss may be disregarded. However, if permeation occurswhen testing in a cell, care has to be taken to ensure contamination does not arise from contact of the simulant withcomponents of the cell.

11 Precision

Precision data enables an assessment of the significance of a test result obtained from tests performed with thestandard test method, and the significance of the result in comparison with a result obtained by another analyst in adifferent laboratory.

The basic precision data which are required for each test method are:

'r' - repeatability value;

'R' - reproducibility value.

NOTE At the time of publication as a Technical Specification precision data is not available.

12 Test reports

12.1 Surface to volume ratios in actual use

12.1.1 General

Overall migration is a measure of inertness and may be expressed in different ways according to the followingcircumstances.

12.1.2 For unknown surface to volume ratios

When the surface to volume ratio in actual use is not known the results obtained under the test conditions shall bereported in milligrams per square decimetre and shall be recalculated to the "conventional" surface to volume ratioof 6 dm² to 1 kg of food and expressed in milligrams per kilogram.

For articles which can be filled and for which it is impracticable to estimate the surface area which is in contact withthe foodstuff the results shall be expressed in milligrams per kilogram.

12.1.3 For known surface to volume ratios and tested under these conditions

When the surface to volume ratio in actual use is known, and the tests have been carried out under theseconditions and the articles are containers or articles which are comparable to containers or which can be filled, witha capacity of not less than 500 ml and not more than 10 l, the results shall be expressed in milligrams per kilogram.

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When the surface to volume ratio in actual use is known, and the tests have been carried out under theseconditions and the articles are not containers or articles which are comparable to containers or which can be filled,with a capacity of not less than 500 ml and not more than 10 l, the results shall be expressed in milligrams persquare decimetre.

12.1.4 For known surface to volume ratios and tested under different conditions

When the surface to volume ratio in actual use is known, but the tests have not been carried out under theseconditions and the articles are containers or articles which are comparable to containers or which can be filled, witha capacity of not less than 500 ml and not more than 10 l, the results shall be recalculated to the actual conditionsof use and expressed in milligrams per kilogram.

When the surface to volume ratio in actual use is known, but the tests have not been carried out under theseconditions and the articles are not containers or articles which are comparable to containers or which can be filled,with a capacity of not less than 500 ml and not more than 10 l, the results shall be expressed in milligrams persquare decimetre.

12.1.5 Conversion recalculation

Where the migration tests are carried out on samples taken from the material or article or on samplesmanufactured for the purpose, and the quantities of foodstuff or simulant placed in contact with the sample differfrom those employed in the actual conditions under which the material or article is used, the results obtained shallbe corrected by applying the following equation:

M = q a a m

1

2

1000(1)

where

M is the migration in milligrams per kilogram;

m is the mass in milligrams of substance released by the sample as determined by the migration test;

a1 is the surface area in square decimetres of the sample in contact with the simulant during themigration test;

a2 is the surface area in square decimetres of the material or article intended to come into contact with foodstuff in real conditions of use;

q is the quantity in grams of foodstuff in contact with the material or article in real conditions of use.

12.2 Reduction factors

Reduction factors are conventionally used for some fatty foodstuffs to take account of the greater extractivecapacity of the fatty food simulant compared to particular categories of foodstuffs. Where the use of a reductionfactor is appropriate, individual test results are divided by the reduction factor before applying the test of validity asdefined in 11.3. The reduction factors appropriate to various food types are to be found in Table 2

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12.3 Validity of results

12.3.1 Aqueous food simulants

The following analytical tolerances are allowed:

6 mg/kg or 1 mg/dm² for all aqueous food simulants.

The test result for each individual test specimen is valid if it differs from the mean of the triplicate test results by notmore than the permitted analytical tolerance. If a minimum of three results is not within the analytical tolerance,then the test is repeated using fresh test specimens from the sample.

A material or article with a mean overall migration result that exceeds the overall migration limit by an amount notexceeding the analytical tolerance, shall be deemed to be in compliance with the overall migration limit.

12.3.2 Fatty food simulants for single use applications

The following analytical tolerances are allowed:

20 mg/kg or 3 mg/dm² for all fatty food simulants and substitute test media.

The tolerances are valid also after application of a reduction factor to the results of the test.

If a reduction factor does not apply, results above 10 mg/dm2 shall not differ by more than 30 % from the mean ofthe set of results.

The determination of overall migration into the fatty food simulant is normally carried out in quadruplicate to allowthree valid results to be obtained even if one determination is discarded.

Where four results have been obtained from four determinations i.e. no single determination has been rejectedbecause of an obvious manipulative error, all four results are valid when if each individual result differs from themean of the four results by not more than the analytical tolerance. If one of the four results is greater or less thanthe mean by an amount more than the tolerance, then this result can be rejected and the mean recalculated on theremaining three results. If two results are greater or less than the mean by amounts more than the tolerance, theresult with the largest difference from the mean can be rejected and a new mean calculated from the remainingthree results. The remaining three test results are valid if they are within the analytical tolerance.

If a minimum of three results do not meet the above criteria of being within the analytical tolerance, then the testshall be repeated using fresh test specimens from the sample.

A material or article with a mean overall migration result that exceeds the overall migration limit by an amount notexceeding the analytical tolerance shall be deemed to be in compliance with the overall migration limit.

12.3.3 Fatty food simulants for repeated use applications

The permitted tolerances are as indicated in 8.8.3.

12.4 Test report

The test report shall include the particulars, required by the relevant Part of this Technical Specification.

12.5 Statements of compliance

When the test reports from the individual tests carried out according to the various Parts of this TechnicalSpecification are collated and related to the limits for overall migration specified, a statement of compliance withregulatory limits may be made. This may include for what types of food and under what conditions of use a articlemay comply with overall migration limits.

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13 Test method for overall migration into aqueous simulants by article filling frompolymeric coatings on food and beverage cans and non-stick coatings

13.1 Scope

This Part of this Technical Specification specifies test methods for the determination of the overall migration intodistilled water and aqueous ethanol food simulants, from polymeric coatings on metal articles in the form ofcontainers, where the polymeric coatings are intended to come into contact with foodstuffs, by filling test specimensof the articles with a selected food simulant at test temperatures up to and including 70 �C for selected test times.

NOTE 1 Experience has shown that acetic acid is not an appropriate food simulant when testing polymeric coatings on metalsubstrates, but 10 % v/v aqueous ethanol has been shown to be acceptable;

NOTE 2 In practice industrial processes use temperatures in excess of 70 �C, commonly 121 �C, and it is recognized thatthis method will need to be extended to cover these conditions or that the conditions need to be covered in a separate testmethod.

13.2 Principle

The overall migration of non-volatile substances from a sample of the metal article with polymeric coating isdetermined as the mass of non-volatile residue after evaporation of the food simulant following filling and exposureof the test specimen.

The selection of the conditions of test will be determined by the conditions of use, see clauses 3, 4, and 5.

Test specimens are filled with the food simulant for the exposure time at temperatures up to and including 70 �C.At the end of the test period each test specimen is emptied. The food simulant from each test specimen isevaporated to dryness, the mass of the non-volatile residue is determined gravimetrically and expressed asmilligrams per square decimetre of surface area exposed to the food simulant.

NOTE In some circumstances the procedure described in this Technical Specification may be used for exposure attemperatures above 70 �C

Overall migration is reported as the mean of three determinations on separate test specimens.

13.3 Reagents

NOTE For details of the preparation and purity of these reagents see clause 4.

13.3.1 Distilled water or water of equivalent quality (simulant A)

13.3.2 Ethanol with a volume fraction of 10 % in aqueous solution (simulant C)

13.3.3 Alcoholic simulants for liquids or beverages of an alcoholic strength exceeding a volume fraction of 10 %.

NOTE In the case of materials and articles intended to come into contact with liquids or beverages of an alcoholic strengthexceeding a volume fraction of 10 %, the test may be carried out with aqueous solutions of ethanol of a similar strength.

13.4 Apparatus

13.4.1 Analytical balance capable of determining a change in mass of 0,1 mg.

13.4.2 Lint-free cloth or soft brush.

13.4.3 Conical flask, 2 l.

13.4.4 Glass beads, 2 mm to 3 mm diameter.

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13.4.5 Thermostatically controlled oven or incubator or refrigerator capable of maintaining the settemperature within the tolerances specified in Table B.2.

13.4.6 Dishes, stainless steel, nickel, platinum, platinum alloy, gold 50 mm to 90 mm diameter and maximumweight 100 g, for evaporation of food simulants and weighing of residues. Glass, glass ceramic or ceramic dishesmay be used, provided that the surface characteristics are such that the weights of the dishes after evaporation ofany specified food simulants followed by conditioning in the desiccator used, achieves a constancy of � 0,5 mg.

13.4.7 Steam bath, hot plate, distillation apparatus or rotary evaporator for evaporation of food simulant at theend of test period.

13.4.8 Desiccator with anhydrous calcium chloride or self indicating silica gel.

13.4.9 Beakers , 250 ml.

13.4.10 Pipette, 200 ml, complying with the minimum requirements of ISO 648.

13.5 Preparation of test specimens

13.5.1 General

It is essential that test specimens are clean and free from surface contamination. Before preparing test specimens,remove any surface contamination from the sample by gently wiping it with a lint free cloth, or by brushing with asoft brush. Under no circumstances wash the sample with water or solvent. If it is specified in the instructions foruse of the article that it should be washed or cleaned before use see 8.1. Minimize handling of the samples and,where necessary, wear cotton gloves.

13.5.2 Number of test specimens

13.5.2.1 Volume of articles

Determine and record the volume of food simulant required to fill an article to its nominal foodstuff volume. If thenominal volume of foodstuff to fill the article is not known, determine the surface area which will be in contact withthe food simulant when filled to 5 mm from the top of the test specimen.

13.5.2.2 Articles with a nominal volume of more than 200 ml

Five articles are required to provide five test specimens. These test specimens are utilized as follows:

a) Three test specimens for the migration test;

b) Two test specimens for the determination of surface area.

13.5.2.3 Articles with a nominal volume of less than 200 ml

The number of articles required to provide a test specimen is dependent on their volume. A test specimen shall bemade up of sufficient articles to contain a minimum of 200 ml of the food simulant.

Five test specimens are required. These test specimens are utilized as follows:

a) Three test specimens for the migration test;

b) Two test specimens for the determination of surface area.

Record the number of articles used to provide the test specimen.

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13.5.3 Surface area of test specimen exposed to food simulant

Determine and record the surface area of the test specimen which is intended to come into contact with its nominalvolume of foodstuff. If the nominal volume of foodstuff to fill the article is not known, determine the surface areawhich will be in contact with the food simulant when filled to 5 mm from the top of the test specimen.

NOTE 1 For some articles it is recognized that it is impractical to measure the surface area intended to come into contactwith foodstuff. For such articles the overall migration is measured as milligrams of substance released per kilogram of foodsimulant.

NOTE 2 In the case of articles with a volume of less than 200 ml this will be the surface area of one article multiplied by thenumber of articles used to provide a test specimen.

13.5.4 Articles with a capacity of not less than 500 ml and not more than 10 l

It is not necessary to determine the volume of these articles since the migration must be expressed in mg/kg offood simulant,

13.6 Procedure

13.6.1 Exposure to food simulant

Mark each test specimen for identification, and where more than one article has been used for a test specimen,also mark individually.

Place, in a conical flask, a sufficient volume of the food simulant to fill the three test specimens to the nominalvolume, if known, or to 5 mm from the top and to provide two 200 ml blanks. Insert a thermometer or thermocouplein the simulant. Place the conical flask in the thermostatically controlled oven or incubator or refrigerator set at thetest temperature and leave until the simulant has attained the test temperature.

Remove the conical flask containing the food simulant from the thermostatically controlled oven or incubator orrefrigerator. Fill the three test specimens with simulant to the nominal volume of the article or to 0,5 cm from thetop. Insert the thermometer or thermocouple in one of the test specimens containing simulant, if applicable - seeNOTE 3. Cover the test specimens with an inert material to prevent evaporation. Stopper the conical flaskcontaining the remaining simulant for the blanks. This filling of the test specimens should be carried out in theminimum time to prevent undue heat loss from the simulant.

Place the test specimens and food simulant for the blanks in the conical flask in the thermostatically controlled ovenor incubator or refrigerator set at the test temperature. Observe the simulant temperature and leave the testspecimens and the blank food simulant for the selected period of time after the temperature of the simulant hasreached a temperature within the permitted tolerance for temperature, see Tables B.1 and B.2 for permittedtolerances on test times and temperature.

NOTE 1 Where the surface area of simulant is large, a check should be made to ensure that excessive loss of simulant byevaporation does not occur.

NOTE 2 Annex B includes tolerances on a wide range of contact times and contact temperatures. All of these contact timesand contact temperatures are not necessarily relevant to this test method.

Take the test specimens and food simulant from the thermostatically controlled oven or incubator or refrigerator.

NOTE 3 For exposure times of 24 h or more it is acceptable to monitor the temperature of the airbath of the thermostaticallycontrolled oven or incubator or refrigerator or instead of the temperature of the simulant.

13.6.2 Determination of migrating substances

13.6.2.1 Preparation of dishes

Take five dishes (12.5.6) marked for identification, place the dishes in an oven maintained at 105 �C to 110 �C, fora period of 30 min � 5 min, to dry.

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Remove the dishes from the oven, place in a desiccator (12.5.8) and allow to cool to ambient temperature. Weighand record the individual masses of each dish.

Replace the dishes in the oven and repeat the cycle of heating, cooling and weighing until individual consecutivemasses differ by no more than 0,5 mg, record their masses.

13.6.2.2 Evaporation method

Take the test specimens and measure from each, by pipette, 200 ml � 2 ml of the simulant into separate 250 mlbeakers, ensuring that the simulant is mixed.

Measure aliquots of 200 ml � 2 ml of the food simulant from the conical flask which had been in the thermostaticallycontrolled oven or incubator or refrigerator with the test specimens, into two more beakers to provide blanks.

Pour 40 ml to 50 ml from each beaker into separate dishes (12.5.6). By means of a steam bath, hot plate or otherform of heating (12.5.7) evaporate to a low volume, taking care to avoid loss, in particular, by sputtering oroverheating of the residues.

NOTE 1 The evaporation of ethanol solutions should be carried out in a fume cupboard.

When most of the simulant has evaporated pour the remaining simulant into the respective dishes. Wash each ofthe beakers with two lots of 10 ml � 1 ml of unused simulant and pour these washings into the respective dishes.Continue the evaporation.

NOTE 2 A stream of nitrogen may be used to facilitate evaporation.

When the simulant in each dish has almost completely evaporated, place the dishes in an oven maintained at 105�C to 110 �C, for a period of 30 min � 5 min, to complete the evaporation and dry the residues.

Remove the dishes from the oven, place in a desiccator (12.5.8) and cool to ambient temperature. Weigh andrecord the individual masses of each dish and residue.

Replace the dishes in the oven and repeat the cycle of heating, cooling and weighing until individual consecutivemasses differ by not more than 0,5 mg.

Determine the mass of the residue in each dish by subtracting the original stable mass of the dish from the stablemass of the dish and residue.

13.6.2.3 Distillation method

Transfer the simulants to individual round bottom flasks (250 ml are suitable). Rinse each test specimen with twolots of 10 ml � 1 ml of unused simulant, add these rinses to the respective flasks. Measure into individual roundbottom flasks two portions of the food simulant equal in volume to the food simulant that has been in contact withthe test specimen plus the rinses, to provide blanks. Place each flask in an electric heating mantle and connect to aside arm distillation arrangement or rotary evaporator. Distil off the simulants until approximately 30 ml to 50 mlremains in each flask. Transfer the remaining simulant in each flask to individual evaporating dishes (12.5.6).Rinse each flask with two lots of 10 ml � 1 ml of fresh simulant and add the rinses to the appropriate dishes.Continue the evaporation of the simulant by means of a steam bath, hot plate or other form of heating, proceedingas in 12.7.2.2.

NOTE The evaporation of ethanol solutions should be carried in a fume cupboard.

13.7 Expression of results

13.7.1 Method of calculation

Express the overall migration as milligrams of residue per square decimetre of the surface of the sample which isintended to come into contact with foodstuffs calculated for each test specimen using the following equation:

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M = S

)m- (m ba 1000 (2)

where

M is the overall migration into the simulant, in milligrams per square decimetre of surface area ofsample;

ma is the mass of the residue from the test specimen after evaporation of the simulant which had filledthe test specimen, in grams;

mb is the mass of residue from the blank simulant equal to the volume which had filled the testspecimen , in grams;

S is the surface area of the test specimen which was in contact with the simulant during the exposurein square decimetres.

Calculate the result for each test specimen to the nearest 0,1 mg/dm² and the mean of the individual test results, tothe nearest 0,1 mg/dm2.

See 11.3 for the directions to determine whether the results are valid.

However, the overall migration shall be expressed in milligrams lost per kilogram of foodstuff in the following cases:

a) articles which are containers or are comparable to containers or which can be filled, with a capacity of not lessthan 500 ml and not more than 10 l;

b) articles which can be filled and for which it is impracticable to estimate the surface area in contact withfoodstuffs;

The overall migration shall be calculated for each test specimen using the following formula:

ML = V

)m- (m ba 1000 (3)

where

ML is the overall migration into the simulant, in milligrams per kilogram of food simulant;

ma is the mass of the residue from the test specimen after evaporation of the simulant which had filledthe article, in grams;

mb is the mass of residue from the blank simulant equal to the volume which had filled the testspecimen, in grams;

V is the volume of simulant that filled of the test specimen in litres,

NOTE The specific gravities are by convention assumed to be 1. Therefore 1 litre of simulant is numerically the same as 1kilogram.

Calculate the result for each test specimen to the nearest 1 mg/kg and the mean of the individual test results, to thenearest 1 mg/kg.


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13.7.1.1 Articles with a volume of more than 200 ml but less than 500 ml; or of a volume greater than 10 l

M = 200

1000 S

V )m- (m ba

(3)

where


ma is the mass of the residue from the test specimen after evaporation of 200 ml of the simulant whichhad filled the article, in grams;

mb is the mass of residue from the food simulant only, in grams;

V is the volume of the food simulant which had filled the article, in millilitres.

S is the surface area of the test specimen which was in contact with the simulant during exposure.

Calculate the result for each test specimen to the nearest 0,1 mg/dm2 d the mean of the individual test results, tothe nearest 0,1 mg/dm2.


13.7.1.2 Articles with a volume of not less than 500 ml and not more than 10 l

ML = 0,2

1000 )m- (m ba (4)

that is

ML = 5000 · (ma - mb) (5)

where

ML is the overall migration into the simulant, in milligrams per kilogram of food simulant;

ma is the mass of the residue from the test specimen after evaporation of 200 ml of the simulant, ingrams;

mb is the mass of residue from the 200 ml of blank simulant, in grams.

Calculate the result for each test specimen to the nearest 1 mg/kg and the mean of the individual test results, to thenearest 1 mg/kg.


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13.7.1.3 Articles with a volume of less than 200 ml

M = N S )m- (m ba

1000 (6)

where:


ma is the mass of the residue from the test specimen after evaporation of the simulant which had filledthe article, in grams;

mb is the mass of residue from the blank simulant equal to the volume which had filled the testspecimen, in grams;

S is the surface area of one test article in square decimetres;

N is the number of articles exposed to the simulant.

Calculate the result for each test specimen to the nearest 0,1 mg/dm2 and the mean of the individual test results, tothe nearest 0,1 mg/dm².


13.7.2 Precision

NOTE The repeatability (r) and the reproducibility (R) values are to be determined from collaborative trial results.

13.8 Test report

The test report shall include the following (see clause 11):

a) reference to this Technical Specification and to the clause used for the test procedure;

b) all information necessary for complete identification of the sample such as chemical type, supplier, trade mark,grade, batch number;

c) conditions of time and temperature of exposure to simulants;

d) departures from the specified procedure, and reasons for these;

e) individual test results, and the mean of these, expressed as milligrams of residue per square decimetre ofsample or as milligrams per kilogram of food simulant as appropriate;

f) relevant comments on the test results.

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Annex A (normative)

Characteristics of fatty food simulants and test media

A.1 Characteristics of rectified olive oil, reference simulant D

iodine value (Wijs) = 80 to 88

refractive index at 25 �C = 1,4665 to 1,4679

acidity, expressed as % oleic acid = 0,5 % maximum

peroxide number, expressed as oxygen milliequivalent per kg of oil = 10 maximum

unsaponifiable matter = < 1 %

A.2 Composition of the mixture of synthetic triglycerides, simulant D

Fatty acid distribution

Number of C-atoms in fatty acid moiety

6 8 10 12 14 16 18 0thers

GLC-area-% �� 6 to 9 8 to 11 45 to 52 12 to 15 8 to 10 8 to 12 � 1

Purity

content of monoglycerides (enzymatically) � 0,2%

content of diglycerides (enzymatically) ��

unsaponifable matter ��

iodine value (Wijs) ��0,1%

acid value ��0,1%

water content (K. Fischer) ��0,1%

melting point 28 �C � 2 �C

Typical absorption spectrum (thickness of layer d=1cm, reference: water, 35 �C)

wavelength (nm) 290 310 330 350 370 390 430 470 510

transmittance (%) ~2 ~15 ~37 ~64 ~80 ~88 ~95 ~97 ~98

at least 10 % light transmittance at 310 nm (cell of 1 cm, reference: water, 35 �C)

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A.3Characteristics of sunflower oil, simulant D

iodine value (Wijs) =120 to 145

refractive index at 20 �C =1,474 to 1,476

saponification number =188 to 193

relative density at 20 �C =0,918 to 0,925

unsaponifiable matter = < 0,5 %

acidity, expressed as oleic acid =< 0,5%

A.4 Characteristics of corn oil, simulant D

iodine value (Wijs) =110 to 135

refractive index at 20 �C = 1,471 to 1,473

acidity, expressed as oleic acid = <0,5%

peroxide number = <10

unsaponifiable matter = < 0,5%

A.5 Characteristics of modified polyphenylene oxide (MPPO)

molecular weight 500,000 to 100,000

size 60 mesh to 80 mesh

T max 350 �C

specific mass 0,23 g/ml

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Annex B (normative)

Limit deviations on contact times and contact temperatures applicable to allclauses of this Technical Specification

Table B.1 — Contact times and limit deviations

Contact times and limitdeviations

+1 30 0 min

+1 60 0 min

+3 90 0 min

+5 120 0 min

+5 150 0 min

+7 180 0 min

+8 210 0 min

+9 240 0 min

+10 270 0 min

+12 300 0 min

+15 360 0 min

+0,5 24 0 h

+0,5 48 0 h

+5 240 0 h

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Table B.2 — Contact temperatures and limit deviations

Contact temperatures and limitdeviations

5 �C � 1 �C

20 �C � 1 �C

30 �C � 1 �C

40 �C � 1 �C

50 �C � 2 �C

60 �C � 2 �C

70 �C � 2 �C

80 �C � 3 �C

90 �C � 3 �C

100 �C � 3 �C

121 �C � 3 �C

130 �C � 5 �C

140 �C � 5 �C

150 �C � 5 �C

160 �C � 5 �C

170 �C � 5 �C

175 �C � 5 �C

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Annex C (normative)

Supports and cells

Dimensions in millimetres

Figure C.1 — Example of support

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Figure C.2 — Example of support

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Key1 Clamp screw2 Clamp bar3 Filler plug4 Plan elevation5 Sealing ring6 Lid7 Food simulant8 Rubber mat9 Base plate10 Side elevation

Figure C.3 — Cell type A

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Key

1 Funnel for filling2 PTFE disk3 PTFE ‘O’-ring (119,5 X � 3)

Figure C.4 — Cell type B

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Key

1 Detail Z

2 ‘O’-ring �117,07/124,13/3,53

Figure C.5 — Cell type C

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1

2

3

5 6

7

89

10

11 12

13

15

14

4

A A

113,9

117,4

Key

1 Glass stopper2 Total inner volume 296ml (max volume ofsimulant 250ml)3 Exposed surface area of circular testspecimens 1,019 dm2

4 Glass bell

11 Glass bell12 Glass stopper13 Tensioning seal (stainless steel)14 Tension ring (stainless steel)15 Sealing ring

5 Sealing ring ('O' ring) silicone rubber sheathed in PTFE6 Raised edge to fix the 'O' ring in place7 Tension ring (stainless steel)8 PTFE plate9 Tensioning seal (stainless steel)10 Sectional view A - A

Figure C.6 — Cell type D

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Figure C.7 — Cell type E

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81

90,5

24

43,5

1

4

2 3 5

6

7

120

Key1 Sealing ring2 Lid (stainless steel)3 Body (aluminium)4 Simulant5 Test sample6 Stopper (PTFE)7 Ring (stainless steel)

Figure C.8 — Cell type F

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Bibliography

[1] Commission of the European Communities, Council Directive of 21 December 1988 on the approximation ofthe laws of the Member States relating to materials and articles intended to come into contact with foodstuff(89/109/EEC), Official Journal of the European Communities, 11 February 1989, no. L 40, p 38.

[2] Commission of the European Communities, Commission Directive of 23 February 1990 relating to plasticsmaterials and articles intended to come into contact with foodstuffs (90/128/EEC), Official Journal of theEuropean Communities, 13 December 1990, no. L349, p26. Corrigendum of the previous publication, OfficialJournal of the European Communities, 21 March 1990, no. 75, p19.

[3] Commission of the European Communities, Council Directive of 18 October 1982 laying down the basic rulesnecessary for testing migration of the constituents of plastics materials and articles intended to come intocontact with foodstuffs (82/711/EEC), Official Journal of the European Communities, 23 October 1982, no. L297, p 26.

[4] Commission of the European Communities, Commission Directive of 15 March 1993 amending CouncilDirective 82/711/EEC laying down the basic rules necessary for testing migration of the constituents of plasticsmaterials and articles intended to come into contact with foodstuffs (93/8/EEC), Official Journal of theEuropean Communities, 14 April 1993, no. L 90, p 22.

[5] Commission of the European Communities, Commission Directive 97/48/EC of 29 July 1997 amendingCouncil Directive 82/711/EEC laying down the basic rules necessary for testing migration of the constituents ofplastics materials and articles intended to come into contact with foodstuffs, Official Journal of the EuropeanCommunities, 12 August 1997, no. L 222, p 10

[6] Commission of the European Communities, Council Directive of 19 December 1985 laying down the list ofsimulants to be used for testing migration of constituents of plastics materials and articles intended to comeinto contact with foodstuffs (85/572/EEC), Official Journal of the European Communities, 31 December 1985,no. L372, p14.

[7] ISO 4788:1980 Laboratory glassware - Graduated measuring cylinders

DD CEN/TS 14235:2002

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